1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2012, 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) =
565 (Specification (Unit_Declaration_Node (Unit_Entity)))
566 and then not In_Package_Body (Unit_Entity)
567 and then not In_Instance;
569 -- What about the case of a nested package in the visible part???
570 -- This case is missed by the List_Containing check above???
571 end In_RCI_Declaration;
573 -----------------------
574 -- In_RT_Declaration --
575 -----------------------
577 function In_RT_Declaration return Boolean is
578 Unit_Entity : constant Entity_Id := Current_Scope;
579 Unit_Kind : constant Node_Kind :=
580 Nkind (Unit (Cunit (Current_Sem_Unit)));
583 -- There are no restrictions on the body of a Remote Types unit
585 return Is_Remote_Types (Unit_Entity)
586 and then Is_Package_Or_Generic_Package (Unit_Entity)
587 and then Unit_Kind /= N_Package_Body
588 and then not In_Package_Body (Unit_Entity)
589 and then not In_Instance;
590 end In_RT_Declaration;
592 ----------------------------
593 -- In_Shared_Passive_Unit --
594 ----------------------------
596 function In_Shared_Passive_Unit return Boolean is
597 Unit_Entity : constant Entity_Id := Current_Scope;
600 return Is_Shared_Passive (Unit_Entity);
601 end In_Shared_Passive_Unit;
603 ---------------------------------------
604 -- In_Subprogram_Task_Protected_Unit --
605 ---------------------------------------
607 function In_Subprogram_Task_Protected_Unit return Boolean is
611 -- The following is to verify that a declaration is inside
612 -- subprogram, generic subprogram, task unit, protected unit.
613 -- Used to validate if a lib. unit is Pure. RM 10.2.1(16).
615 -- Use scope chain to check successively outer scopes
621 Is_Generic_Subprogram (E)
623 Is_Concurrent_Type (E)
627 elsif E = Standard_Standard then
633 end In_Subprogram_Task_Protected_Unit;
635 -------------------------------
636 -- Is_Non_Remote_Access_Type --
637 -------------------------------
639 function Is_Non_Remote_Access_Type (E : Entity_Id) return Boolean is
640 U_E : constant Entity_Id := Underlying_Type (E);
644 -- This case arises for the case of a generic formal type, in which
645 -- case E.2.2(8) rules will be enforced at instantiation time.
650 return Is_Access_Type (U_E)
651 and then not Is_Remote_Access_To_Class_Wide_Type (U_E)
652 and then not Is_Remote_Access_To_Subprogram_Type (U_E);
653 end Is_Non_Remote_Access_Type;
655 ---------------------------
656 -- No_External_Streaming --
657 ---------------------------
659 function No_External_Streaming (E : Entity_Id) return Boolean is
660 U_E : constant Entity_Id := Underlying_Type (E);
666 elsif Has_Read_Write_Attributes (E) then
668 -- Note: availability of stream attributes is tested on E, not U_E.
669 -- There may be stream attributes defined on U_E that are not visible
670 -- at the place where support of external streaming is tested.
674 elsif Has_Non_Remote_Access (U_E) then
678 return Is_Limited_Type (E);
679 end No_External_Streaming;
681 -------------------------------------
682 -- Set_Categorization_From_Pragmas --
683 -------------------------------------
685 procedure Set_Categorization_From_Pragmas (N : Node_Id) is
686 P : constant Node_Id := Parent (N);
687 S : constant Entity_Id := Current_Scope;
689 procedure Set_Parents (Visibility : Boolean);
690 -- If this is a child instance, the parents are not immediately
691 -- visible during analysis. Make them momentarily visible so that
692 -- the argument of the pragma can be resolved properly, and reset
699 procedure Set_Parents (Visibility : Boolean) is
703 while Present (Par) and then Par /= Standard_Standard loop
704 Set_Is_Immediately_Visible (Par, Visibility);
709 -- Start of processing for Set_Categorization_From_Pragmas
712 -- Deal with categorization pragmas in Pragmas of Compilation_Unit.
713 -- The purpose is to set categorization flags before analyzing the
714 -- unit itself, so as to diagnose violations of categorization as
715 -- we process each declaration, even though the pragma appears after
718 if Nkind (P) /= N_Compilation_Unit then
726 if Is_Child_Unit (S) and then Is_Generic_Instance (S) then
730 PN := First (Pragmas_After (Aux_Decls_Node (P)));
731 while Present (PN) loop
733 -- Skip implicit types that may have been introduced by
734 -- previous analysis.
736 if Nkind (PN) = N_Pragma then
737 case Get_Pragma_Id (PN) is
738 when Pragma_All_Calls_Remote |
739 Pragma_Preelaborate |
741 Pragma_Remote_Call_Interface |
742 Pragma_Remote_Types |
743 Pragma_Shared_Passive => Analyze (PN);
751 if Is_Child_Unit (S) and then Is_Generic_Instance (S) then
755 end Set_Categorization_From_Pragmas;
757 -----------------------------------
758 -- Set_Categorization_From_Scope --
759 -----------------------------------
761 procedure Set_Categorization_From_Scope (E : Entity_Id; Scop : Entity_Id) is
762 Declaration : Node_Id := Empty;
763 Specification : Node_Id := Empty;
767 (E, Is_Pure (Scop) and then Is_Library_Level_Entity (E));
769 if not Is_Remote_Call_Interface (E) then
770 if Ekind (E) in Subprogram_Kind then
771 Declaration := Unit_Declaration_Node (E);
773 if Nkind_In (Declaration, N_Subprogram_Body,
774 N_Subprogram_Renaming_Declaration)
776 Specification := Corresponding_Spec (Declaration);
780 -- A subprogram body or renaming-as-body is a remote call interface
781 -- if it serves as the completion of a subprogram declaration that
782 -- is a remote call interface.
784 if Nkind (Specification) in N_Entity then
785 Set_Is_Remote_Call_Interface
786 (E, Is_Remote_Call_Interface (Specification));
788 -- A subprogram declaration is a remote call interface when it is
789 -- declared within the visible part of, or declared by, a library
790 -- unit declaration that is a remote call interface.
793 Set_Is_Remote_Call_Interface
794 (E, Is_Remote_Call_Interface (Scop)
795 and then not (In_Private_Part (Scop)
796 or else In_Package_Body (Scop)));
801 (E, Is_Remote_Types (Scop)
802 and then not (In_Private_Part (Scop)
803 or else In_Package_Body (Scop)));
804 end Set_Categorization_From_Scope;
806 ------------------------------
807 -- Static_Discriminant_Expr --
808 ------------------------------
810 -- We need to accommodate a Why_Not_Static call somehow here ???
812 function Static_Discriminant_Expr (L : List_Id) return Boolean is
813 Discriminant_Spec : Node_Id;
816 Discriminant_Spec := First (L);
817 while Present (Discriminant_Spec) loop
818 if Present (Expression (Discriminant_Spec))
819 and then not Is_Static_Expression (Expression (Discriminant_Spec))
824 Next (Discriminant_Spec);
828 end Static_Discriminant_Expr;
830 --------------------------------------
831 -- Validate_Access_Type_Declaration --
832 --------------------------------------
834 procedure Validate_Access_Type_Declaration (T : Entity_Id; N : Node_Id) is
835 Def : constant Node_Id := Type_Definition (N);
840 -- Access to subprogram case
842 when N_Access_To_Subprogram_Definition =>
844 -- A pure library_item must not contain the declaration of a
845 -- named access type, except within a subprogram, generic
846 -- subprogram, task unit, or protected unit (RM 10.2.1(16)).
848 -- This test is skipped in Ada 2005 (see AI-366)
850 if Ada_Version < Ada_2005
851 and then Comes_From_Source (T)
852 and then In_Pure_Unit
853 and then not In_Subprogram_Task_Protected_Unit
855 Error_Msg_N ("named access type not allowed in pure unit", T);
858 -- Access to object case
860 when N_Access_To_Object_Definition =>
861 if Comes_From_Source (T)
862 and then In_Pure_Unit
863 and then not In_Subprogram_Task_Protected_Unit
865 -- We can't give the message yet, since the type is not frozen
866 -- and in Ada 2005 mode, access types are allowed in pure units
867 -- if the type has no storage pool (see AI-366). So we set a
868 -- flag which will be checked at freeze time.
870 Set_Is_Pure_Unit_Access_Type (T);
873 -- Check for RCI or RT unit type declaration: declaration of an
874 -- access-to-object type is illegal unless it is a general access
875 -- type that designates a class-wide limited private type.
876 -- Note that constraints on the primitive subprograms of the
877 -- designated tagged type are not enforced here but in
878 -- Validate_RACW_Primitives, which is done separately because the
879 -- designated type might not be frozen (and therefore its
880 -- primitive operations might not be completely known) at the
881 -- point of the RACW declaration.
883 Validate_Remote_Access_Object_Type_Declaration (T);
885 -- Check for shared passive unit type declaration. It should
886 -- not contain the declaration of access to class wide type,
887 -- access to task type and access to protected type with entry.
889 Validate_SP_Access_Object_Type_Decl (T);
895 -- Set categorization flag from package on entity as well, to allow
896 -- easy checks later on for required validations of RCI or RT units.
897 -- This is only done for entities that are in the original source.
899 if Comes_From_Source (T)
900 and then not (In_Package_Body (Scope (T))
901 or else In_Private_Part (Scope (T)))
903 Set_Is_Remote_Call_Interface
904 (T, Is_Remote_Call_Interface (Scope (T)));
906 (T, Is_Remote_Types (Scope (T)));
908 end Validate_Access_Type_Declaration;
910 ----------------------------
911 -- Validate_Ancestor_Part --
912 ----------------------------
914 procedure Validate_Ancestor_Part (N : Node_Id) is
915 A : constant Node_Id := Ancestor_Part (N);
916 T : constant Entity_Id := Entity (A);
919 if In_Preelaborated_Unit
920 and then not In_Subprogram_Or_Concurrent_Unit
921 and then (not Inside_A_Generic
922 or else Present (Enclosing_Generic_Body (N)))
924 -- If the type is private, it must have the Ada 2005 pragma
925 -- Has_Preelaborable_Initialization.
927 -- The check is omitted within predefined units. This is probably
928 -- obsolete code to fix the Ada 95 weakness in this area ???
930 if Is_Private_Type (T)
931 and then not Has_Pragma_Preelab_Init (T)
932 and then not Is_Internal_File_Name
933 (Unit_File_Name (Get_Source_Unit (N)))
936 ("private ancestor type not allowed in preelaborated unit", A);
938 elsif Is_Record_Type (T) then
939 if Nkind (Parent (T)) = N_Full_Type_Declaration then
940 Check_Non_Static_Default_Expr
941 (Type_Definition (Parent (T)), A);
945 end Validate_Ancestor_Part;
947 ----------------------------------------
948 -- Validate_Categorization_Dependency --
949 ----------------------------------------
951 procedure Validate_Categorization_Dependency
955 K : constant Node_Kind := Nkind (N);
956 P : Node_Id := Parent (N);
958 Is_Subunit : constant Boolean := Nkind (P) = N_Subunit;
961 -- Only validate library units and subunits. For subunits, checks
962 -- concerning withed units apply to the parent compilation unit.
969 and then not Is_Compilation_Unit (U)
970 and then not Is_Child_Unit (U)
976 if Nkind (P) /= N_Compilation_Unit then
980 -- Body of RCI unit does not need validation
982 if Is_Remote_Call_Interface (E)
983 and then Nkind_In (N, N_Package_Body, N_Subprogram_Body)
988 -- Ada 2005 (AI-50217): Process explicit non-limited with_clauses
992 Entity_Of_Withed : Entity_Id;
995 Item := First (Context_Items (P));
996 while Present (Item) loop
997 if Nkind (Item) = N_With_Clause
998 and then not (Implicit_With (Item)
999 or else Limited_Present (Item)
1001 -- Skip if error already posted on the WITH
1002 -- clause (in which case the Name attribute
1003 -- may be invalid). In particular, this fixes
1004 -- the problem of hanging in the presence of a
1005 -- WITH clause on a child that is an illegal
1006 -- generic instantiation.
1008 or else Error_Posted (Item))
1010 Entity_Of_Withed := Entity (Name (Item));
1011 Check_Categorization_Dependencies
1012 (U, Entity_Of_Withed, Item, Is_Subunit);
1019 -- Child depends on parent; therefore parent should also be categorized
1020 -- and satisfy the dependency hierarchy.
1022 -- Check if N is a child spec
1024 if (K in N_Generic_Declaration or else
1025 K in N_Generic_Instantiation or else
1026 K in N_Generic_Renaming_Declaration or else
1027 K = N_Package_Declaration or else
1028 K = N_Package_Renaming_Declaration or else
1029 K = N_Subprogram_Declaration or else
1030 K = N_Subprogram_Renaming_Declaration)
1031 and then Present (Parent_Spec (N))
1033 Check_Categorization_Dependencies (E, Scope (E), N, False);
1035 -- Verify that public child of an RCI library unit must also be an
1036 -- RCI library unit (RM E.2.3(15)).
1038 if Is_Remote_Call_Interface (Scope (E))
1039 and then not Private_Present (P)
1040 and then not Is_Remote_Call_Interface (E)
1042 Error_Msg_N ("public child of rci unit must also be rci unit", N);
1045 end Validate_Categorization_Dependency;
1047 --------------------------------
1048 -- Validate_Controlled_Object --
1049 --------------------------------
1051 procedure Validate_Controlled_Object (E : Entity_Id) is
1053 -- Don't need this check in Ada 2005 mode, where this is all taken
1054 -- care of by the mechanism for Preelaborable Initialization.
1056 if Ada_Version >= Ada_2005 then
1060 -- For now, never apply this check for internal GNAT units, since we
1061 -- have a number of cases in the library where we are stuck with objects
1062 -- of this type, and the RM requires Preelaborate.
1064 -- For similar reasons, we only do this check for source entities, since
1065 -- we generate entities of this type in some situations.
1067 -- Note that the 10.2.1(9) restrictions are not relevant to us anyway.
1068 -- We have to enforce them for RM compatibility, but we have no trouble
1069 -- accepting these objects and doing the right thing. Note that there is
1070 -- no requirement that Preelaborate not actually generate any code!
1072 if In_Preelaborated_Unit
1073 and then not Debug_Flag_PP
1074 and then Comes_From_Source (E)
1076 Is_Internal_File_Name (Unit_File_Name (Get_Source_Unit (E)))
1077 and then (not Inside_A_Generic
1078 or else Present (Enclosing_Generic_Body (E)))
1079 and then not Is_Protected_Type (Etype (E))
1082 ("library level controlled object not allowed in " &
1083 "preelaborated unit", E);
1085 end Validate_Controlled_Object;
1087 --------------------------------------
1088 -- Validate_Null_Statement_Sequence --
1089 --------------------------------------
1091 procedure Validate_Null_Statement_Sequence (N : Node_Id) is
1095 if In_Preelaborated_Unit then
1096 Item := First (Statements (Handled_Statement_Sequence (N)));
1097 while Present (Item) loop
1098 if Nkind (Item) /= N_Label
1099 and then Nkind (Item) /= N_Null_Statement
1101 -- In GNAT mode, this is a warning, allowing the run-time
1102 -- to judiciously bypass this error condition.
1104 Error_Msg_Warn := GNAT_Mode;
1106 ("<statements not allowed in preelaborated unit", Item);
1114 end Validate_Null_Statement_Sequence;
1116 ---------------------------------
1117 -- Validate_Object_Declaration --
1118 ---------------------------------
1120 procedure Validate_Object_Declaration (N : Node_Id) is
1121 Id : constant Entity_Id := Defining_Identifier (N);
1122 E : constant Node_Id := Expression (N);
1123 Odf : constant Node_Id := Object_Definition (N);
1124 T : constant Entity_Id := Etype (Id);
1127 -- Verify that any access to subprogram object does not have in its
1128 -- subprogram profile access type parameters or limited parameters
1129 -- without Read and Write attributes (E.2.3(13)).
1131 Validate_RCI_Subprogram_Declaration (N);
1133 -- Check that if we are in preelaborated elaboration code, then we
1134 -- do not have an instance of a default initialized private, task or
1135 -- protected object declaration which would violate (RM 10.2.1(9)).
1136 -- Note that constants are never default initialized (and the test
1137 -- below also filters out deferred constants). A variable is default
1138 -- initialized if it does *not* have an initialization expression.
1140 -- Filter out cases that are not declaration of a variable from source
1142 if Nkind (N) /= N_Object_Declaration
1143 or else Constant_Present (N)
1144 or else not Comes_From_Source (Id)
1149 -- Exclude generic specs from the checks (this will get rechecked
1150 -- on instantiations).
1152 if Inside_A_Generic and then No (Enclosing_Generic_Body (Id)) then
1156 -- Required checks for declaration that is in a preelaborated package
1157 -- and is not within some subprogram.
1159 if In_Preelaborated_Unit
1160 and then not In_Subprogram_Or_Concurrent_Unit
1162 -- Check for default initialized variable case. Note that in
1163 -- accordance with (RM B.1(24)) imported objects are not subject to
1164 -- default initialization.
1165 -- If the initialization does not come from source and is an
1166 -- aggregate, it is a static initialization that replaces an
1167 -- implicit call, and must be treated as such.
1170 and then (Comes_From_Source (E) or else Nkind (E) /= N_Aggregate)
1174 elsif Is_Imported (Id) then
1179 Ent : Entity_Id := T;
1182 -- An array whose component type is a record with nonstatic
1183 -- default expressions is a violation, so we get the array's
1186 if Is_Array_Type (Ent) then
1188 Comp_Type : Entity_Id;
1191 Comp_Type := Component_Type (Ent);
1192 while Is_Array_Type (Comp_Type) loop
1193 Comp_Type := Component_Type (Comp_Type);
1200 -- Object decl. that is of record type and has no default expr.
1201 -- should check if there is any non-static default expression
1202 -- in component decl. of the record type decl.
1204 if Is_Record_Type (Ent) then
1205 if Nkind (Parent (Ent)) = N_Full_Type_Declaration then
1206 Check_Non_Static_Default_Expr
1207 (Type_Definition (Parent (Ent)), N);
1209 elsif Nkind (Odf) = N_Subtype_Indication
1210 and then not Is_Array_Type (T)
1211 and then not Is_Private_Type (T)
1213 Check_Non_Static_Default_Expr (Type_Definition
1214 (Parent (Entity (Subtype_Mark (Odf)))), N);
1218 -- Check for invalid use of private object. Note that Ada 2005
1219 -- AI-161 modifies the rules for Ada 2005, including the use of
1220 -- the new pragma Preelaborable_Initialization.
1222 if Is_Private_Type (Ent)
1223 or else Depends_On_Private (Ent)
1225 -- Case where type has preelaborable initialization which
1226 -- means that a pragma Preelaborable_Initialization was
1227 -- given for the private type.
1229 if Has_Preelaborable_Initialization (Ent) then
1231 -- But for the predefined units, we will ignore this
1232 -- status unless we are in Ada 2005 mode since we want
1233 -- Ada 95 compatible behavior, in which the entities
1234 -- marked with this pragma in the predefined library are
1235 -- not treated specially.
1237 if Ada_Version < Ada_2005 then
1239 ("private object not allowed in preelaborated unit",
1241 Error_Msg_N ("\(would be legal in Ada 2005 mode)", N);
1244 -- Type does not have preelaborable initialization
1247 -- We allow this when compiling in GNAT mode to make life
1248 -- easier for some cases where it would otherwise be hard
1249 -- to be exactly valid Ada.
1251 if not GNAT_Mode then
1253 ("private object not allowed in preelaborated unit",
1256 -- Add a message if it would help to provide a pragma
1257 -- Preelaborable_Initialization on the type of the
1258 -- object (which would make it legal in Ada 2005).
1260 -- If the type has no full view (generic type, or
1261 -- previous error), the warning does not apply.
1263 if Is_Private_Type (Ent)
1264 and then Present (Full_View (Ent))
1266 Has_Preelaborable_Initialization (Full_View (Ent))
1268 Error_Msg_Sloc := Sloc (Ent);
1270 if Ada_Version >= Ada_2005 then
1272 ("\would be legal if pragma Preelaborable_" &
1273 "Initialization given for & #", N, Ent);
1276 ("\would be legal in Ada 2005 if pragma " &
1277 "Preelaborable_Initialization given for & #",
1284 -- Access to Task or Protected type
1286 elsif Is_Entity_Name (Odf)
1287 and then Present (Etype (Odf))
1288 and then Is_Access_Type (Etype (Odf))
1290 Ent := Designated_Type (Etype (Odf));
1292 elsif Is_Entity_Name (Odf) then
1293 Ent := Entity (Odf);
1295 elsif Nkind (Odf) = N_Subtype_Indication then
1296 Ent := Etype (Subtype_Mark (Odf));
1298 elsif Nkind (Odf) = N_Constrained_Array_Definition then
1299 Ent := Component_Type (T);
1302 if Is_Task_Type (Ent)
1303 or else (Is_Protected_Type (Ent) and then Has_Entries (Ent))
1306 ("concurrent object not allowed in preelaborated unit",
1313 -- Non-static discriminants not allowed in preelaborated unit.
1314 -- Objects of a controlled type with a user-defined Initialize
1315 -- are forbidden as well.
1317 if Is_Record_Type (Etype (Id)) then
1319 ET : constant Entity_Id := Etype (Id);
1320 EE : constant Entity_Id := Etype (Etype (Id));
1324 if Has_Discriminants (ET) and then Present (EE) then
1327 if Nkind (PEE) = N_Full_Type_Declaration
1328 and then not Static_Discriminant_Expr
1329 (Discriminant_Specifications (PEE))
1332 ("non-static discriminant in preelaborated unit",
1337 -- For controlled type or type with controlled component, check
1338 -- preelaboration flag, as there may be a non-null Initialize
1339 -- primitive. For language versions earlier than Ada 2005,
1340 -- there is no notion of preelaborable initialization, and
1341 -- Validate_Controlled_Object is used to enforce rules for
1342 -- controlled objects.
1344 if (Is_Controlled (ET) or else Has_Controlled_Component (ET))
1345 and then Ada_Version >= Ada_2005
1346 and then not Has_Preelaborable_Initialization (ET)
1349 ("controlled type& does not have"
1350 & " preelaborable initialization", N, ET);
1357 -- A pure library_item must not contain the declaration of any variable
1358 -- except within a subprogram, generic subprogram, task unit, or
1359 -- protected unit (RM 10.2.1(16)).
1361 if In_Pure_Unit and then not In_Subprogram_Task_Protected_Unit then
1362 Error_Msg_N ("declaration of variable not allowed in pure unit", N);
1364 -- The visible part of an RCI library unit must not contain the
1365 -- declaration of a variable (RM E.1.3(9))
1367 elsif In_RCI_Declaration (N) then
1368 Error_Msg_N ("visible variable not allowed in 'R'C'I unit", N);
1370 -- The visible part of a Shared Passive library unit must not contain
1371 -- the declaration of a variable (RM E.2.2(7))
1373 elsif In_RT_Declaration and then not In_Private_Part (Id) then
1375 ("visible variable not allowed in remote types unit", N);
1378 end Validate_Object_Declaration;
1380 -----------------------------
1381 -- Validate_RACW_Primitive --
1382 -----------------------------
1384 procedure Validate_RACW_Primitive
1388 procedure Illegal_Remote_Subp (Msg : String; N : Node_Id);
1389 -- Diagnose illegality on N. If RACW is present, report the error on it
1390 -- rather than on N.
1392 -------------------------
1393 -- Illegal_Remote_Subp --
1394 -------------------------
1396 procedure Illegal_Remote_Subp (Msg : String; N : Node_Id) is
1398 if Present (RACW) then
1399 if not Error_Posted (RACW) then
1401 ("illegal remote access to class-wide type&", RACW);
1404 Error_Msg_Sloc := Sloc (N);
1405 Error_Msg_NE ("\\" & Msg & " in primitive& #", RACW, Subp);
1408 Error_Msg_NE (Msg & " in remote subprogram&", N, Subp);
1410 end Illegal_Remote_Subp;
1414 Param_Spec : Node_Id;
1415 Param_Type : Entity_Id;
1417 -- Start of processing for Validate_RACW_Primitive
1420 -- Check return type
1422 if Ekind (Subp) = E_Function then
1423 Rtyp := Etype (Subp);
1425 -- AI05-0101 (Binding Interpretation): The result type of a remote
1426 -- function must either support external streaming or be a
1427 -- controlling access result type.
1429 if Has_Controlling_Result (Subp) then
1432 elsif Ekind (Rtyp) = E_Anonymous_Access_Type then
1433 Illegal_Remote_Subp ("anonymous access result", Rtyp);
1435 elsif Is_Limited_Type (Rtyp) then
1436 if No (TSS (Rtyp, TSS_Stream_Read))
1438 No (TSS (Rtyp, TSS_Stream_Write))
1441 ("limited return type must have Read and Write attributes",
1443 Explain_Limited_Type (Rtyp, Parent (Subp));
1446 -- Check that the return type supports external streaming
1448 elsif No_External_Streaming (Rtyp)
1449 and then not Error_Posted (Rtyp)
1451 Illegal_Remote_Subp ("return type containing non-remote access "
1452 & "must have Read and Write attributes",
1457 Param := First_Formal (Subp);
1458 while Present (Param) loop
1460 -- Now find out if this parameter is a controlling parameter
1462 Param_Spec := Parent (Param);
1463 Param_Type := Etype (Param);
1465 if Is_Controlling_Formal (Param) then
1467 -- It is a controlling parameter, so specific checks below do not
1472 elsif Ekind_In (Param_Type, E_Anonymous_Access_Type,
1473 E_Anonymous_Access_Subprogram_Type)
1475 -- From RM E.2.2(14), no anonymous access parameter other than
1476 -- controlling ones may be used (because an anonymous access
1477 -- type never supports external streaming).
1480 ("non-controlling access parameter", Param_Spec);
1482 elsif No_External_Streaming (Param_Type)
1483 and then not Error_Posted (Param_Type)
1485 Illegal_Remote_Subp ("formal parameter in remote subprogram must "
1486 & "support external streaming", Param_Spec);
1489 -- Check next parameter in this subprogram
1491 Next_Formal (Param);
1493 end Validate_RACW_Primitive;
1495 ------------------------------
1496 -- Validate_RACW_Primitives --
1497 ------------------------------
1499 procedure Validate_RACW_Primitives (T : Entity_Id) is
1500 Desig_Type : Entity_Id;
1501 Primitive_Subprograms : Elist_Id;
1502 Subprogram_Elmt : Elmt_Id;
1503 Subprogram : Entity_Id;
1506 Desig_Type := Etype (Designated_Type (T));
1508 -- No action needed for concurrent types
1510 if Is_Concurrent_Type (Desig_Type) then
1514 Primitive_Subprograms := Primitive_Operations (Desig_Type);
1516 Subprogram_Elmt := First_Elmt (Primitive_Subprograms);
1517 while Subprogram_Elmt /= No_Elmt loop
1518 Subprogram := Node (Subprogram_Elmt);
1520 if Is_Predefined_Dispatching_Operation (Subprogram)
1521 or else Is_Hidden (Subprogram)
1523 goto Next_Subprogram;
1526 Validate_RACW_Primitive (Subp => Subprogram, RACW => T);
1529 Next_Elmt (Subprogram_Elmt);
1531 end Validate_RACW_Primitives;
1533 -------------------------------
1534 -- Validate_RCI_Declarations --
1535 -------------------------------
1537 procedure Validate_RCI_Declarations (P : Entity_Id) is
1541 E := First_Entity (P);
1542 while Present (E) loop
1543 if Comes_From_Source (E) then
1544 if Is_Limited_Type (E) then
1546 ("limited type not allowed in rci unit", Parent (E));
1547 Explain_Limited_Type (E, Parent (E));
1549 elsif Ekind_In (E, E_Generic_Function,
1551 E_Generic_Procedure)
1553 Error_Msg_N ("generic declaration not allowed in rci unit",
1556 elsif (Ekind (E) = E_Function or else Ekind (E) = E_Procedure)
1557 and then Has_Pragma_Inline (E)
1560 ("inlined subprogram not allowed in rci unit", Parent (E));
1562 -- Inner packages that are renamings need not be checked. Generic
1563 -- RCI packages are subject to the checks, but entities that come
1564 -- from formal packages are not part of the visible declarations
1565 -- of the package and are not checked.
1567 elsif Ekind (E) = E_Package then
1568 if Present (Renamed_Entity (E)) then
1571 elsif Ekind (P) /= E_Generic_Package
1572 or else List_Containing (Unit_Declaration_Node (E)) /=
1573 Generic_Formal_Declarations
1574 (Unit_Declaration_Node (P))
1576 Validate_RCI_Declarations (E);
1583 end Validate_RCI_Declarations;
1585 -----------------------------------------
1586 -- Validate_RCI_Subprogram_Declaration --
1587 -----------------------------------------
1589 procedure Validate_RCI_Subprogram_Declaration (N : Node_Id) is
1590 K : constant Node_Kind := Nkind (N);
1593 Param_Spec : Node_Id;
1594 Param_Type : Entity_Id;
1595 Error_Node : Node_Id := N;
1598 -- This procedure enforces rules on subprogram and access to subprogram
1599 -- declarations in RCI units. These rules do not apply to expander
1600 -- generated routines, which are not remote subprograms. It is called:
1602 -- 1. from Analyze_Subprogram_Declaration.
1603 -- 2. from Validate_Object_Declaration (access to subprogram).
1605 if not (Comes_From_Source (N) and then In_RCI_Declaration (N)) then
1609 if K = N_Subprogram_Declaration then
1610 Id := Defining_Unit_Name (Specification (N));
1611 Profile := Parameter_Specifications (Specification (N));
1613 else pragma Assert (K = N_Object_Declaration);
1615 -- The above assertion is dubious, the visible declarations of an
1616 -- RCI unit never contain an object declaration, this should be an
1617 -- ACCESS-to-object declaration???
1619 Id := Defining_Identifier (N);
1621 if Nkind (Id) = N_Defining_Identifier
1622 and then Nkind (Parent (Etype (Id))) = N_Full_Type_Declaration
1623 and then Ekind (Etype (Id)) = E_Access_Subprogram_Type
1626 Parameter_Specifications (Type_Definition (Parent (Etype (Id))));
1632 -- Iterate through the parameter specification list, checking that
1633 -- no access parameter and no limited type parameter in the list.
1636 if Present (Profile) then
1637 Param_Spec := First (Profile);
1638 while Present (Param_Spec) loop
1639 Param_Type := Etype (Defining_Identifier (Param_Spec));
1641 if Ekind (Param_Type) = E_Anonymous_Access_Type then
1642 if K = N_Subprogram_Declaration then
1643 Error_Node := Param_Spec;
1646 -- Report error only if declaration is in source program
1648 if Comes_From_Source
1649 (Defining_Entity (Specification (N)))
1652 ("subprogram in 'R'C'I unit cannot have access parameter",
1656 -- For a limited private type parameter, we check only the private
1657 -- declaration and ignore full type declaration, unless this is
1658 -- the only declaration for the type, e.g., as a limited record.
1660 elsif No_External_Streaming (Param_Type) then
1661 if K = N_Subprogram_Declaration then
1662 Error_Node := Param_Spec;
1666 ("formal of remote subprogram& "
1667 & "must support external streaming",
1669 if Is_Limited_Type (Param_Type) then
1670 Explain_Limited_Type (Param_Type, Error_Node);
1677 -- No check on return type???
1679 end Validate_RCI_Subprogram_Declaration;
1681 ----------------------------------------------------
1682 -- Validate_Remote_Access_Object_Type_Declaration --
1683 ----------------------------------------------------
1685 procedure Validate_Remote_Access_Object_Type_Declaration (T : Entity_Id) is
1686 Direct_Designated_Type : Entity_Id;
1687 Desig_Type : Entity_Id;
1690 -- We are called from Analyze_Full_Type_Declaration, and the Nkind of
1691 -- the given node is N_Access_To_Object_Definition.
1693 if not Comes_From_Source (T)
1694 or else (not In_RCI_Declaration (Parent (T))
1695 and then not In_RT_Declaration)
1700 -- An access definition in the private part of a Remote Types package
1701 -- may be legal if it has user-defined Read and Write attributes. This
1702 -- will be checked at the end of the package spec processing.
1704 if In_RT_Declaration and then In_Private_Part (Scope (T)) then
1708 -- Check RCI or RT unit type declaration. It may not contain the
1709 -- declaration of an access-to-object type unless it is a general access
1710 -- type that designates a class-wide limited private type or subtype.
1711 -- There are also constraints on the primitive subprograms of the
1712 -- class-wide type (RM E.2.2(14), see Validate_RACW_Primitives).
1714 if Ekind (T) /= E_General_Access_Type
1715 or else not Is_Class_Wide_Type (Designated_Type (T))
1717 if In_RCI_Declaration (Parent (T)) then
1719 ("error in access type in Remote_Call_Interface unit", T);
1722 ("error in access type in Remote_Types unit", T);
1725 Error_Msg_N ("\must be general access to class-wide type", T);
1729 Direct_Designated_Type := Designated_Type (T);
1730 Desig_Type := Etype (Direct_Designated_Type);
1732 -- Why is this check not in Validate_Remote_Access_To_Class_Wide_Type???
1734 if not Is_Valid_Remote_Object_Type (Desig_Type) then
1736 ("error in designated type of remote access to class-wide type", T);
1738 ("\must be tagged limited private or private extension", T);
1741 end Validate_Remote_Access_Object_Type_Declaration;
1743 -----------------------------------------------
1744 -- Validate_Remote_Access_To_Class_Wide_Type --
1745 -----------------------------------------------
1747 procedure Validate_Remote_Access_To_Class_Wide_Type (N : Node_Id) is
1748 K : constant Node_Kind := Nkind (N);
1749 PK : constant Node_Kind := Nkind (Parent (N));
1753 -- This subprogram enforces the checks in (RM E.2.2(8)) for certain uses
1754 -- of class-wide limited private types.
1756 -- Storage_Pool and Storage_Size are not defined for such types
1758 -- The expected type of allocator must not be such a type.
1760 -- The actual parameter of generic instantiation must not be such a
1761 -- type if the formal parameter is of an access type.
1763 -- On entry, there are several cases:
1765 -- 1. called from sem_attr Analyze_Attribute where attribute name is
1766 -- either Storage_Pool or Storage_Size.
1768 -- 2. called from exp_ch4 Expand_N_Allocator
1770 -- 3. called from sem_ch4 Analyze_Explicit_Dereference
1772 -- 4. called from sem_res Resolve_Actuals
1774 if K = N_Attribute_Reference then
1775 E := Etype (Prefix (N));
1777 if Is_Remote_Access_To_Class_Wide_Type (E) then
1778 Error_Msg_N ("incorrect attribute of remote operand", N);
1782 elsif K = N_Allocator then
1785 if Is_Remote_Access_To_Class_Wide_Type (E) then
1786 Error_Msg_N ("incorrect expected remote type of allocator", N);
1790 -- This subprogram also enforces the checks in E.2.2(13). A value of
1791 -- such type must not be dereferenced unless as controlling operand of
1792 -- a dispatching call. Explicit dereferences not coming from source are
1793 -- exempted from this checking because the expander produces them in
1794 -- some cases (such as for tag checks on dispatching calls with multiple
1795 -- controlling operands). However we do check in the case of an implicit
1796 -- dereference that is expanded to an explicit dereference (hence the
1797 -- test of whether Original_Node (N) comes from source).
1799 elsif K = N_Explicit_Dereference
1800 and then Comes_From_Source (Original_Node (N))
1802 E := Etype (Prefix (N));
1804 -- If the class-wide type is not a remote one, the restrictions
1807 if not Is_Remote_Access_To_Class_Wide_Type (E) then
1811 -- If we have a true dereference that comes from source and that
1812 -- is a controlling argument for a dispatching call, accept it.
1814 if Is_Actual_Parameter (N) and then Is_Controlling_Actual (N) then
1818 -- If we are just within a procedure or function call and the
1819 -- dereference has not been analyzed, return because this procedure
1820 -- will be called again from sem_res Resolve_Actuals. The same can
1821 -- apply in the case of dereference that is the prefix of a selected
1822 -- component, which can be a call given in prefixed form.
1824 if (Is_Actual_Parameter (N) or else PK = N_Selected_Component)
1825 and then not Analyzed (N)
1830 -- We must allow expanded code to generate a reference to the tag of
1831 -- the designated object (may be either the actual tag, or the stub
1832 -- tag in the case of a remote object).
1834 if PK = N_Selected_Component
1835 and then Is_Tag (Entity (Selector_Name (Parent (N))))
1841 ("invalid dereference of a remote access-to-class-wide value", N);
1843 end Validate_Remote_Access_To_Class_Wide_Type;
1845 ------------------------------------------
1846 -- Validate_Remote_Type_Type_Conversion --
1847 ------------------------------------------
1849 procedure Validate_Remote_Type_Type_Conversion (N : Node_Id) is
1850 S : constant Entity_Id := Etype (N);
1851 E : constant Entity_Id := Etype (Expression (N));
1854 -- This test is required in the case where a conversion appears inside a
1855 -- normal package, it does not necessarily have to be inside an RCI,
1856 -- Remote_Types unit (RM E.2.2(9,12)).
1858 if Is_Remote_Access_To_Subprogram_Type (E)
1859 and then not Is_Remote_Access_To_Subprogram_Type (S)
1862 ("incorrect conversion of remote operand to local type", N);
1865 elsif not Is_Remote_Access_To_Subprogram_Type (E)
1866 and then Is_Remote_Access_To_Subprogram_Type (S)
1869 ("incorrect conversion of local operand to remote type", N);
1872 elsif Is_Remote_Access_To_Class_Wide_Type (E)
1873 and then not Is_Remote_Access_To_Class_Wide_Type (S)
1876 ("incorrect conversion of remote operand to local type", N);
1880 -- If a local access type is converted into a RACW type, then the
1881 -- current unit has a pointer that may now be exported to another
1884 if Is_Remote_Access_To_Class_Wide_Type (S)
1885 and then not Is_Remote_Access_To_Class_Wide_Type (E)
1887 Set_Has_RACW (Current_Sem_Unit);
1889 end Validate_Remote_Type_Type_Conversion;
1891 -------------------------------
1892 -- Validate_RT_RAT_Component --
1893 -------------------------------
1895 procedure Validate_RT_RAT_Component (N : Node_Id) is
1896 Spec : constant Node_Id := Specification (N);
1897 Name_U : constant Entity_Id := Defining_Entity (Spec);
1900 First_Priv_Ent : constant Entity_Id := First_Private_Entity (Name_U);
1902 function Stream_Attributes_Available (Typ : Entity_Id) return Boolean;
1903 -- True if any stream attribute is available for Typ
1905 ---------------------------------
1906 -- Stream_Attributes_Available --
1907 ---------------------------------
1909 function Stream_Attributes_Available (Typ : Entity_Id) return Boolean
1912 return Stream_Attribute_Available (Typ, TSS_Stream_Read)
1914 Stream_Attribute_Available (Typ, TSS_Stream_Write)
1916 Stream_Attribute_Available (Typ, TSS_Stream_Input)
1918 Stream_Attribute_Available (Typ, TSS_Stream_Output);
1919 end Stream_Attributes_Available;
1921 -- Start of processing for Validate_RT_RAT_Component
1924 if not Is_Remote_Types (Name_U) then
1928 Typ := First_Entity (Name_U);
1929 while Present (Typ) and then Typ /= First_Priv_Ent loop
1930 U_Typ := Underlying_Type (Typ);
1936 if Comes_From_Source (Typ) and then Is_Type (Typ) then
1938 -- Check that the type can be meaningfully transmitted to another
1939 -- partition (E.2.2(8)).
1941 if (Ada_Version < Ada_2005 and then Has_Non_Remote_Access (U_Typ))
1942 or else (Stream_Attributes_Available (Typ)
1943 and then No_External_Streaming (U_Typ))
1945 if Is_Non_Remote_Access_Type (Typ) then
1946 Error_Msg_N ("error in non-remote access type", U_Typ);
1949 ("error in record type containing a component of a " &
1950 "non-remote access type", U_Typ);
1953 if Ada_Version >= Ada_2005 then
1955 ("\must have visible Read and Write attribute " &
1956 "definition clauses (RM E.2.2(8))", U_Typ);
1959 ("\must have Read and Write attribute " &
1960 "definition clauses (RM E.2.2(8))", U_Typ);
1967 end Validate_RT_RAT_Component;
1969 -----------------------------------------
1970 -- Validate_SP_Access_Object_Type_Decl --
1971 -----------------------------------------
1973 procedure Validate_SP_Access_Object_Type_Decl (T : Entity_Id) is
1974 Direct_Designated_Type : Entity_Id;
1976 function Has_Entry_Declarations (E : Entity_Id) return Boolean;
1977 -- Return true if the protected type designated by T has entry
1980 ----------------------------
1981 -- Has_Entry_Declarations --
1982 ----------------------------
1984 function Has_Entry_Declarations (E : Entity_Id) return Boolean is
1988 if Nkind (Parent (E)) = N_Protected_Type_Declaration then
1989 Ety := First_Entity (E);
1990 while Present (Ety) loop
1991 if Ekind (Ety) = E_Entry then
2000 end Has_Entry_Declarations;
2002 -- Start of processing for Validate_SP_Access_Object_Type_Decl
2005 -- We are called from Sem_Ch3.Analyze_Full_Type_Declaration, and the
2006 -- Nkind of the given entity is N_Access_To_Object_Definition.
2008 if not Comes_From_Source (T)
2009 or else not In_Shared_Passive_Unit
2010 or else In_Subprogram_Task_Protected_Unit
2015 -- Check Shared Passive unit. It should not contain the declaration
2016 -- of an access-to-object type whose designated type is a class-wide
2017 -- type, task type or protected type with entry (RM E.2.1(7)).
2019 Direct_Designated_Type := Designated_Type (T);
2021 if Ekind (Direct_Designated_Type) = E_Class_Wide_Type then
2023 ("invalid access-to-class-wide type in shared passive unit", T);
2026 elsif Ekind (Direct_Designated_Type) in Task_Kind then
2028 ("invalid access-to-task type in shared passive unit", T);
2031 elsif Ekind (Direct_Designated_Type) in Protected_Kind
2032 and then Has_Entry_Declarations (Direct_Designated_Type)
2035 ("invalid access-to-protected type in shared passive unit", T);
2038 end Validate_SP_Access_Object_Type_Decl;
2040 ---------------------------------
2041 -- Validate_Static_Object_Name --
2042 ---------------------------------
2044 procedure Validate_Static_Object_Name (N : Node_Id) is
2047 function Is_Primary (N : Node_Id) return Boolean;
2048 -- Determine whether node is syntactically a primary in an expression
2049 -- This function should probably be somewhere else ???
2051 -- Also it does not do what it says, e.g if N is a binary operator
2052 -- whose parent is a binary operator, Is_Primary returns True ???
2058 function Is_Primary (N : Node_Id) return Boolean is
2059 K : constant Node_Kind := Nkind (Parent (N));
2063 when N_Op | N_Membership_Test =>
2067 | N_Component_Association
2068 | N_Index_Or_Discriminant_Constraint =>
2071 when N_Attribute_Reference =>
2072 return Attribute_Name (Parent (N)) /= Name_Address
2073 and then Attribute_Name (Parent (N)) /= Name_Access
2074 and then Attribute_Name (Parent (N)) /= Name_Unchecked_Access
2076 Attribute_Name (Parent (N)) /= Name_Unrestricted_Access;
2078 when N_Indexed_Component =>
2079 return (N /= Prefix (Parent (N))
2080 or else Is_Primary (Parent (N)));
2082 when N_Qualified_Expression | N_Type_Conversion =>
2083 return Is_Primary (Parent (N));
2085 when N_Assignment_Statement | N_Object_Declaration =>
2086 return (N = Expression (Parent (N)));
2088 when N_Selected_Component =>
2089 return Is_Primary (Parent (N));
2096 -- Start of processing for Validate_Static_Object_Name
2099 if not In_Preelaborated_Unit
2100 or else not Comes_From_Source (N)
2101 or else In_Subprogram_Or_Concurrent_Unit
2102 or else Ekind (Current_Scope) = E_Block
2106 -- Filter out cases where primary is default in a component declaration,
2107 -- discriminant specification, or actual in a record type initialization
2110 -- Initialization call of internal types
2112 elsif Nkind (Parent (N)) = N_Procedure_Call_Statement then
2114 if Present (Parent (Parent (N)))
2115 and then Nkind (Parent (Parent (N))) = N_Freeze_Entity
2120 if Nkind (Name (Parent (N))) = N_Identifier
2121 and then not Comes_From_Source (Entity (Name (Parent (N))))
2127 -- Error if the name is a primary in an expression. The parent must not
2128 -- be an operator, or a selected component or an indexed component that
2129 -- is itself a primary. Entities that are actuals do not need to be
2130 -- checked, because the call itself will be diagnosed.
2133 and then (not Inside_A_Generic
2134 or else Present (Enclosing_Generic_Body (N)))
2136 if Ekind (Entity (N)) = E_Variable
2137 or else Ekind (Entity (N)) in Formal_Object_Kind
2139 Flag_Non_Static_Expr
2140 ("non-static object name in preelaborated unit", N);
2142 -- Give an error for a reference to a nonstatic constant, unless the
2143 -- constant is in another GNAT library unit that is preelaborable.
2145 elsif Ekind (Entity (N)) = E_Constant
2146 and then not Is_Static_Expression (N)
2150 if Is_Internal_File_Name (Unit_File_Name (Get_Source_Unit (N)))
2152 Enclosing_Comp_Unit_Node (N) /= Enclosing_Comp_Unit_Node (E)
2153 and then (Is_Preelaborated (Scope (E))
2154 or else Is_Pure (Scope (E))
2155 or else (Present (Renamed_Object (E))
2156 and then Is_Entity_Name (Renamed_Object (E))
2159 (Scope (Renamed_Object (E)))
2162 (Renamed_Object (E))))))
2166 -- This is the error case
2169 -- In GNAT mode, this is just a warning, to allow it to be
2170 -- judiciously turned off. Otherwise it is a real error.
2174 ("??non-static constant in preelaborated unit", N);
2176 Flag_Non_Static_Expr
2177 ("non-static constant in preelaborated unit", N);
2182 end Validate_Static_Object_Name;