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Diffstat (limited to 'gcc-4.4.0/gcc/ada/sem_cat.adb')
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diff --git a/gcc-4.4.0/gcc/ada/sem_cat.adb b/gcc-4.4.0/gcc/ada/sem_cat.adb deleted file mode 100644 index 273c04f81..000000000 --- a/gcc-4.4.0/gcc/ada/sem_cat.adb +++ /dev/null @@ -1,2231 +0,0 @@ ------------------------------------------------------------------------------- --- -- --- GNAT COMPILER COMPONENTS -- --- -- --- S E M _ C A T -- --- -- --- B o d y -- --- -- --- Copyright (C) 1992-2008, Free Software Foundation, Inc. -- --- -- --- GNAT is free software; you can redistribute it and/or modify it under -- --- terms of the GNU General Public License as published by the Free Soft- -- --- ware Foundation; either version 3, or (at your option) any later ver- -- --- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- --- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- --- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- --- for more details. You should have received a copy of the GNU General -- --- Public License distributed with GNAT; see file COPYING3. If not, go to -- --- http://www.gnu.org/licenses for a complete copy of the license. -- --- -- --- GNAT was originally developed by the GNAT team at New York University. -- --- Extensive contributions were provided by Ada Core Technologies Inc. -- --- -- ------------------------------------------------------------------------------- - -with Atree; use Atree; -with Debug; use Debug; -with Einfo; use Einfo; -with Elists; use Elists; -with Errout; use Errout; -with Exp_Disp; use Exp_Disp; -with Fname; use Fname; -with Lib; use Lib; -with Namet; use Namet; -with Nlists; use Nlists; -with Opt; use Opt; -with Sem; use Sem; -with Sem_Eval; use Sem_Eval; -with Sem_Util; use Sem_Util; -with Sinfo; use Sinfo; -with Snames; use Snames; -with Stand; use Stand; - -package body Sem_Cat is - - ----------------------- - -- Local Subprograms -- - ----------------------- - - procedure Check_Categorization_Dependencies - (Unit_Entity : Entity_Id; - Depended_Entity : Entity_Id; - Info_Node : Node_Id; - Is_Subunit : Boolean); - -- This procedure checks that the categorization of a lib unit and that - -- of the depended unit satisfy dependency restrictions. - -- The depended_entity can be the entity in a with_clause item, in which - -- case Info_Node denotes that item. The depended_entity can also be the - -- parent unit of a child unit, in which case Info_Node is the declaration - -- of the child unit. The error message is posted on Info_Node, and is - -- specialized if Is_Subunit is true. - - procedure Check_Non_Static_Default_Expr - (Type_Def : Node_Id; - Obj_Decl : Node_Id); - -- Iterate through the component list of a record definition, check - -- that no component is declared with a nonstatic default value. - -- If a nonstatic default exists, report an error on Obj_Decl. - - -- Iterate through the component list of a record definition, check - -- that no component is declared with a non-static default value. - - function Missing_Read_Write_Attributes (E : Entity_Id) return Boolean; - -- Return True if the entity or one of its subcomponents is of an access - -- type that does not have user-defined Read and Write attributes visible - -- at any place. - - function In_RCI_Declaration (N : Node_Id) return Boolean; - -- Determines if a declaration is within the visible part of a Remote - -- Call Interface compilation unit, for semantic checking purposes only, - -- (returns false within an instance and within the package body). - - function In_RT_Declaration return Boolean; - -- Determines if current scope is within a Remote Types compilation unit, - -- for semantic checking purposes. - - function Is_Non_Remote_Access_Type (E : Entity_Id) return Boolean; - -- Returns true if the entity is a type whose full view is a non-remote - -- access type, for the purpose of enforcing E.2.2(8) rules. - - function In_Shared_Passive_Unit return Boolean; - -- Determines if current scope is within a Shared Passive compilation unit - - function Static_Discriminant_Expr (L : List_Id) return Boolean; - -- Iterate through the list of discriminants to check if any of them - -- contains non-static default expression, which is a violation in - -- a preelaborated library unit. - - procedure Validate_Remote_Access_Object_Type_Declaration (T : Entity_Id); - -- Check validity of declaration if RCI or RT unit. It should not contain - -- the declaration of an access-to-object type unless it is a general - -- access type that designates a class-wide limited private type. There are - -- also constraints about the primitive subprograms of the class-wide type. - -- RM E.2 (9, 13, 14) - - --------------------------------------- - -- Check_Categorization_Dependencies -- - --------------------------------------- - - procedure Check_Categorization_Dependencies - (Unit_Entity : Entity_Id; - Depended_Entity : Entity_Id; - Info_Node : Node_Id; - Is_Subunit : Boolean) - is - N : constant Node_Id := Info_Node; - - -- Here we define an enumeration type to represent categorization types, - -- ordered so that a unit with a given categorization can only WITH - -- units with lower or equal categorization type. - - -- Note that we take advantage of E.2(14) to define a category - -- Preelaborated and treat pragma Preelaborate as a categorization - -- pragma that defines that category. - - type Categorization is - (Pure, - Shared_Passive, - Remote_Types, - Remote_Call_Interface, - Preelaborated, - Normal); - - function Get_Categorization (E : Entity_Id) return Categorization; - -- Check categorization flags from entity, and return in the form - -- of the lowest value of the Categorization type that applies to E. - - ------------------------ - -- Get_Categorization -- - ------------------------ - - function Get_Categorization (E : Entity_Id) return Categorization is - begin - -- Get the lowest categorization that corresponds to E. Note that - -- nothing prevents several (different) categorization pragmas - -- to apply to the same library unit, in which case the unit has - -- all associated categories, so we need to be careful here to - -- check pragmas in proper Categorization order in order to - -- return the lowest applicable value. - - -- Ignore Pure specification if set by pragma Pure_Function - - if Is_Pure (E) - and then not - (Has_Pragma_Pure_Function (E) and not Has_Pragma_Pure (E)) - then - return Pure; - - elsif Is_Shared_Passive (E) then - return Shared_Passive; - - elsif Is_Remote_Types (E) then - return Remote_Types; - - elsif Is_Remote_Call_Interface (E) then - return Remote_Call_Interface; - - elsif Is_Preelaborated (E) then - return Preelaborated; - - else - return Normal; - end if; - end Get_Categorization; - - Unit_Category : Categorization; - With_Category : Categorization; - - -- Start of processing for Check_Categorization_Dependencies - - begin - -- Intrinsic subprograms are preelaborated, so do not impose any - -- categorization dependencies. - - if Is_Intrinsic_Subprogram (Depended_Entity) then - return; - end if; - - Unit_Category := Get_Categorization (Unit_Entity); - With_Category := Get_Categorization (Depended_Entity); - - -- These messages are warnings in GNAT mode, to allow it to be - -- judiciously turned off. Otherwise it is a real error. - - Error_Msg_Warn := GNAT_Mode; - - -- Check for possible error - - if With_Category > Unit_Category then - - -- Special case: Remote_Types and Remote_Call_Interface are allowed - -- to be with'ed in package body. - - if (Unit_Category = Remote_Types - or else Unit_Category = Remote_Call_Interface) - and then In_Package_Body (Unit_Entity) - then - null; - - -- Here we have an error - - else - -- Don't give error if main unit is not an internal unit, and the - -- unit generating the message is an internal unit. This is the - -- situation in which such messages would be ignored in any case, - -- so it is convenient not to generate them (since it causes - -- annoying interference with debugging). - - if Is_Internal_File_Name (Unit_File_Name (Current_Sem_Unit)) - and then not Is_Internal_File_Name (Unit_File_Name (Main_Unit)) - then - return; - - -- Subunit case - - elsif Is_Subunit then - Error_Msg_NE - ("<subunit cannot depend on& " & - "(parent has wrong categorization)", N, Depended_Entity); - - -- Normal unit, not subunit - - else - Error_Msg_NE - ("<cannot depend on& " & - "(wrong categorization)", N, Depended_Entity); - end if; - - -- Add further explanation for common cases - - case Unit_Category is - when Pure => - Error_Msg_NE - ("\<pure unit cannot depend on non-pure unit", - N, Depended_Entity); - - when Preelaborated => - Error_Msg_NE - ("\<preelaborated unit cannot depend on " & - "non-preelaborated unit", - N, Depended_Entity); - - when others => - null; - end case; - end if; - end if; - end Check_Categorization_Dependencies; - - ----------------------------------- - -- Check_Non_Static_Default_Expr -- - ----------------------------------- - - procedure Check_Non_Static_Default_Expr - (Type_Def : Node_Id; - Obj_Decl : Node_Id) - is - Recdef : Node_Id; - Component_Decl : Node_Id; - - begin - if Nkind (Type_Def) = N_Derived_Type_Definition then - Recdef := Record_Extension_Part (Type_Def); - - if No (Recdef) then - return; - end if; - - else - Recdef := Type_Def; - end if; - - -- Check that component declarations do not involve: - - -- a. a non-static default expression, where the object is - -- declared to be default initialized. - - -- b. a dynamic Itype (discriminants and constraints) - - if Null_Present (Recdef) then - return; - else - Component_Decl := First (Component_Items (Component_List (Recdef))); - end if; - - while Present (Component_Decl) - and then Nkind (Component_Decl) = N_Component_Declaration - loop - if Present (Expression (Component_Decl)) - and then Nkind (Expression (Component_Decl)) /= N_Null - and then not Is_Static_Expression (Expression (Component_Decl)) - then - Error_Msg_Sloc := Sloc (Component_Decl); - Error_Msg_F - ("object in preelaborated unit has non-static default#", - Obj_Decl); - - -- Fix this later ??? - - -- elsif Has_Dynamic_Itype (Component_Decl) then - -- Error_Msg_N - -- ("dynamic type discriminant," & - -- " constraint in preelaborated unit", - -- Component_Decl); - end if; - - Next (Component_Decl); - end loop; - end Check_Non_Static_Default_Expr; - - ------------------------------------- - -- Has_Stream_Attribute_Definition -- - ------------------------------------- - - function Has_Stream_Attribute_Definition - (Typ : Entity_Id; - Nam : TSS_Name_Type; - At_Any_Place : Boolean := False) return Boolean - is - Rep_Item : Node_Id; - Full_Type : Entity_Id := Typ; - - begin - -- In the case of a type derived from a private view, any specified - -- stream attributes will be attached to the derived type's underlying - -- type rather the derived type entity itself (which is itself private). - - if Is_Private_Type (Typ) - and then Is_Derived_Type (Typ) - and then Present (Full_View (Typ)) - then - Full_Type := Underlying_Type (Typ); - end if; - - -- We start from the declaration node and then loop until the end of - -- the list until we find the requested attribute definition clause. - -- In Ada 2005 mode, clauses are ignored if they are not currently - -- visible (this is tested using the corresponding Entity, which is - -- inserted by the expander at the point where the clause occurs), - -- unless At_Any_Place is true. - - Rep_Item := First_Rep_Item (Full_Type); - while Present (Rep_Item) loop - if Nkind (Rep_Item) = N_Attribute_Definition_Clause then - case Chars (Rep_Item) is - when Name_Read => - exit when Nam = TSS_Stream_Read; - - when Name_Write => - exit when Nam = TSS_Stream_Write; - - when Name_Input => - exit when Nam = TSS_Stream_Input; - - when Name_Output => - exit when Nam = TSS_Stream_Output; - - when others => - null; - - end case; - end if; - - Next_Rep_Item (Rep_Item); - end loop; - - -- If At_Any_Place is true, return True if the attribute is available - -- at any place; if it is false, return True only if the attribute is - -- currently visible. - - return Present (Rep_Item) - and then (Ada_Version < Ada_05 - or else At_Any_Place - or else not Is_Hidden (Entity (Rep_Item))); - end Has_Stream_Attribute_Definition; - - --------------------------- - -- In_Preelaborated_Unit -- - --------------------------- - - function In_Preelaborated_Unit return Boolean is - Unit_Entity : constant Entity_Id := Current_Scope; - Unit_Kind : constant Node_Kind := - Nkind (Unit (Cunit (Current_Sem_Unit))); - - begin - -- There are no constraints on body of remote_call_interface or - -- remote_types packages. - - return (Unit_Entity /= Standard_Standard) - and then (Is_Preelaborated (Unit_Entity) - or else Is_Pure (Unit_Entity) - or else Is_Shared_Passive (Unit_Entity) - or else - ((Is_Remote_Types (Unit_Entity) - or else Is_Remote_Call_Interface (Unit_Entity)) - and then Ekind (Unit_Entity) = E_Package - and then Unit_Kind /= N_Package_Body - and then not In_Package_Body (Unit_Entity) - and then not In_Instance)); - end In_Preelaborated_Unit; - - ------------------ - -- In_Pure_Unit -- - ------------------ - - function In_Pure_Unit return Boolean is - begin - return Is_Pure (Current_Scope); - end In_Pure_Unit; - - ------------------------ - -- In_RCI_Declaration -- - ------------------------ - - function In_RCI_Declaration (N : Node_Id) return Boolean is - Unit_Entity : constant Entity_Id := Current_Scope; - Unit_Kind : constant Node_Kind := - Nkind (Unit (Cunit (Current_Sem_Unit))); - - begin - -- There are no restrictions on the private part or body - -- of an RCI unit. - - return Is_Remote_Call_Interface (Unit_Entity) - and then Is_Package_Or_Generic_Package (Unit_Entity) - and then Unit_Kind /= N_Package_Body - and then List_Containing (N) = - Visible_Declarations - (Specification (Unit_Declaration_Node (Unit_Entity))) - and then not In_Package_Body (Unit_Entity) - and then not In_Instance; - - -- What about the case of a nested package in the visible part??? - -- This case is missed by the List_Containing check above??? - end In_RCI_Declaration; - - ----------------------- - -- In_RT_Declaration -- - ----------------------- - - function In_RT_Declaration return Boolean is - Unit_Entity : constant Entity_Id := Current_Scope; - Unit_Kind : constant Node_Kind := - Nkind (Unit (Cunit (Current_Sem_Unit))); - - begin - -- There are no restrictions on the body of a Remote Types unit - - return Is_Remote_Types (Unit_Entity) - and then Is_Package_Or_Generic_Package (Unit_Entity) - and then Unit_Kind /= N_Package_Body - and then not In_Package_Body (Unit_Entity) - and then not In_Instance; - end In_RT_Declaration; - - ---------------------------- - -- In_Shared_Passive_Unit -- - ---------------------------- - - function In_Shared_Passive_Unit return Boolean is - Unit_Entity : constant Entity_Id := Current_Scope; - - begin - return Is_Shared_Passive (Unit_Entity); - end In_Shared_Passive_Unit; - - --------------------------------------- - -- In_Subprogram_Task_Protected_Unit -- - --------------------------------------- - - function In_Subprogram_Task_Protected_Unit return Boolean is - E : Entity_Id; - - begin - -- The following is to verify that a declaration is inside - -- subprogram, generic subprogram, task unit, protected unit. - -- Used to validate if a lib. unit is Pure. RM 10.2.1(16). - - -- Use scope chain to check successively outer scopes - - E := Current_Scope; - loop - if Is_Subprogram (E) - or else - Is_Generic_Subprogram (E) - or else - Is_Concurrent_Type (E) - then - return True; - - elsif E = Standard_Standard then - return False; - end if; - - E := Scope (E); - end loop; - end In_Subprogram_Task_Protected_Unit; - - ------------------------------- - -- Is_Non_Remote_Access_Type -- - ------------------------------- - - function Is_Non_Remote_Access_Type (E : Entity_Id) return Boolean is - U_E : constant Entity_Id := Underlying_Type (E); - begin - if No (U_E) then - - -- This case arises for the case of a generic formal type, in which - -- case E.2.2(8) rules will be enforced at instantiation time. - - return False; - end if; - - return Is_Access_Type (U_E) - and then not Is_Remote_Access_To_Class_Wide_Type (U_E) - and then not Is_Remote_Access_To_Subprogram_Type (U_E); - end Is_Non_Remote_Access_Type; - - ---------------------------------- - -- Missing_Read_Write_Attribute -- - ---------------------------------- - - function Missing_Read_Write_Attributes (E : Entity_Id) return Boolean is - Component : Entity_Id; - Component_Type : Entity_Id; - U_E : constant Entity_Id := Underlying_Type (E); - - function Has_Read_Write_Attributes (E : Entity_Id) return Boolean; - -- Return True if entity has attribute definition clauses for Read and - -- Write attributes that are visible at some place. - - ------------------------------- - -- Has_Read_Write_Attributes -- - ------------------------------- - - function Has_Read_Write_Attributes (E : Entity_Id) return Boolean is - begin - return True - and then Has_Stream_Attribute_Definition (E, - TSS_Stream_Read, At_Any_Place => True) - and then Has_Stream_Attribute_Definition (E, - TSS_Stream_Write, At_Any_Place => True); - end Has_Read_Write_Attributes; - - -- Start of processing for Missing_Read_Write_Attributes - - begin - if No (U_E) then - return False; - - elsif Has_Read_Write_Attributes (E) - or else Has_Read_Write_Attributes (U_E) - then - return False; - - elsif Is_Non_Remote_Access_Type (U_E) then - return True; - end if; - - if Is_Record_Type (U_E) then - Component := First_Entity (U_E); - while Present (Component) loop - if not Is_Tag (Component) then - Component_Type := Etype (Component); - - if Missing_Read_Write_Attributes (Component_Type) then - return True; - end if; - end if; - - Next_Entity (Component); - end loop; - end if; - - return False; - end Missing_Read_Write_Attributes; - - ------------------------------------- - -- Set_Categorization_From_Pragmas -- - ------------------------------------- - - procedure Set_Categorization_From_Pragmas (N : Node_Id) is - P : constant Node_Id := Parent (N); - S : constant Entity_Id := Current_Scope; - - procedure Set_Parents (Visibility : Boolean); - -- If this is a child instance, the parents are not immediately - -- visible during analysis. Make them momentarily visible so that - -- the argument of the pragma can be resolved properly, and reset - -- afterwards. - - ----------------- - -- Set_Parents -- - ----------------- - - procedure Set_Parents (Visibility : Boolean) is - Par : Entity_Id; - begin - Par := Scope (S); - while Present (Par) and then Par /= Standard_Standard loop - Set_Is_Immediately_Visible (Par, Visibility); - Par := Scope (Par); - end loop; - end Set_Parents; - - -- Start of processing for Set_Categorization_From_Pragmas - - begin - -- Deal with categorization pragmas in Pragmas of Compilation_Unit. - -- The purpose is to set categorization flags before analyzing the - -- unit itself, so as to diagnose violations of categorization as - -- we process each declaration, even though the pragma appears after - -- the unit. - - if Nkind (P) /= N_Compilation_Unit then - return; - end if; - - declare - PN : Node_Id; - - begin - if Is_Child_Unit (S) - and then Is_Generic_Instance (S) - then - Set_Parents (True); - end if; - - PN := First (Pragmas_After (Aux_Decls_Node (P))); - while Present (PN) loop - - -- Skip implicit types that may have been introduced by - -- previous analysis. - - if Nkind (PN) = N_Pragma then - case Get_Pragma_Id (PN) is - when Pragma_All_Calls_Remote | - Pragma_Preelaborate | - Pragma_Pure | - Pragma_Remote_Call_Interface | - Pragma_Remote_Types | - Pragma_Shared_Passive => Analyze (PN); - when others => null; - end case; - end if; - - Next (PN); - end loop; - - if Is_Child_Unit (S) - and then Is_Generic_Instance (S) - then - Set_Parents (False); - end if; - end; - end Set_Categorization_From_Pragmas; - - ----------------------------------- - -- Set_Categorization_From_Scope -- - ----------------------------------- - - procedure Set_Categorization_From_Scope (E : Entity_Id; Scop : Entity_Id) is - Declaration : Node_Id := Empty; - Specification : Node_Id := Empty; - - begin - Set_Is_Pure (E, - Is_Pure (Scop) and then Is_Library_Level_Entity (E)); - - if not Is_Remote_Call_Interface (E) then - if Ekind (E) in Subprogram_Kind then - Declaration := Unit_Declaration_Node (E); - - if Nkind (Declaration) = N_Subprogram_Body - or else - Nkind (Declaration) = N_Subprogram_Renaming_Declaration - then - Specification := Corresponding_Spec (Declaration); - end if; - end if; - - -- A subprogram body or renaming-as-body is a remote call - -- interface if it serves as the completion of a subprogram - -- declaration that is a remote call interface. - - if Nkind (Specification) in N_Entity then - Set_Is_Remote_Call_Interface - (E, Is_Remote_Call_Interface (Specification)); - - -- A subprogram declaration is a remote call interface when it is - -- declared within the visible part of, or declared by, a library - -- unit declaration that is a remote call interface. - - else - Set_Is_Remote_Call_Interface - (E, Is_Remote_Call_Interface (Scop) - and then not (In_Private_Part (Scop) - or else In_Package_Body (Scop))); - end if; - end if; - - Set_Is_Remote_Types - (E, Is_Remote_Types (Scop) - and then not (In_Private_Part (Scop) - or else In_Package_Body (Scop))); - end Set_Categorization_From_Scope; - - ------------------------------ - -- Static_Discriminant_Expr -- - ------------------------------ - - -- We need to accommodate a Why_Not_Static call somehow here ??? - - function Static_Discriminant_Expr (L : List_Id) return Boolean is - Discriminant_Spec : Node_Id; - - begin - Discriminant_Spec := First (L); - while Present (Discriminant_Spec) loop - if Present (Expression (Discriminant_Spec)) - and then not Is_Static_Expression (Expression (Discriminant_Spec)) - then - return False; - end if; - - Next (Discriminant_Spec); - end loop; - - return True; - end Static_Discriminant_Expr; - - -------------------------------------- - -- Validate_Access_Type_Declaration -- - -------------------------------------- - - procedure Validate_Access_Type_Declaration (T : Entity_Id; N : Node_Id) is - Def : constant Node_Id := Type_Definition (N); - - begin - case Nkind (Def) is - - -- Access to subprogram case - - when N_Access_To_Subprogram_Definition => - - -- A pure library_item must not contain the declaration of a - -- named access type, except within a subprogram, generic - -- subprogram, task unit, or protected unit (RM 10.2.1(16)). - - -- This test is skipped in Ada 2005 (see AI-366) - - if Ada_Version < Ada_05 - and then Comes_From_Source (T) - and then In_Pure_Unit - and then not In_Subprogram_Task_Protected_Unit - then - Error_Msg_N ("named access type not allowed in pure unit", T); - end if; - - -- Access to object case - - when N_Access_To_Object_Definition => - if Comes_From_Source (T) - and then In_Pure_Unit - and then not In_Subprogram_Task_Protected_Unit - then - -- We can't give the message yet, since the type is not frozen - -- and in Ada 2005 mode, access types are allowed in pure units - -- if the type has no storage pool (see AI-366). So we set a - -- flag which will be checked at freeze time. - - Set_Is_Pure_Unit_Access_Type (T); - end if; - - -- Check for RCI or RT unit type declaration: declaration of an - -- access-to-object type is illegal unless it is a general access - -- type that designates a class-wide limited private type. - -- Note that constraints on the primitive subprograms of the - -- designated tagged type are not enforced here but in - -- Validate_RACW_Primitives, which is done separately because the - -- designated type might not be frozen (and therefore its - -- primitive operations might not be completely known) at the - -- point of the RACW declaration. - - Validate_Remote_Access_Object_Type_Declaration (T); - - -- Check for shared passive unit type declaration. It should - -- not contain the declaration of access to class wide type, - -- access to task type and access to protected type with entry. - - Validate_SP_Access_Object_Type_Decl (T); - - when others => - null; - end case; - - -- Set categorization flag from package on entity as well, to allow - -- easy checks later on for required validations of RCI or RT units. - -- This is only done for entities that are in the original source. - - if Comes_From_Source (T) - and then not (In_Package_Body (Scope (T)) - or else In_Private_Part (Scope (T))) - then - Set_Is_Remote_Call_Interface - (T, Is_Remote_Call_Interface (Scope (T))); - Set_Is_Remote_Types - (T, Is_Remote_Types (Scope (T))); - end if; - end Validate_Access_Type_Declaration; - - ---------------------------- - -- Validate_Ancestor_Part -- - ---------------------------- - - procedure Validate_Ancestor_Part (N : Node_Id) is - A : constant Node_Id := Ancestor_Part (N); - T : constant Entity_Id := Entity (A); - - begin - if In_Preelaborated_Unit - and then not In_Subprogram_Or_Concurrent_Unit - and then (not Inside_A_Generic - or else Present (Enclosing_Generic_Body (N))) - then - -- If the type is private, it must have the Ada 2005 pragma - -- Has_Preelaborable_Initialization. - -- The check is omitted within predefined units. This is probably - -- obsolete code to fix the Ada95 weakness in this area ??? - - if Is_Private_Type (T) - and then not Has_Pragma_Preelab_Init (T) - and then not Is_Internal_File_Name - (Unit_File_Name (Get_Source_Unit (N))) - then - Error_Msg_N - ("private ancestor type not allowed in preelaborated unit", A); - - elsif Is_Record_Type (T) then - if Nkind (Parent (T)) = N_Full_Type_Declaration then - Check_Non_Static_Default_Expr - (Type_Definition (Parent (T)), A); - end if; - end if; - end if; - end Validate_Ancestor_Part; - - ---------------------------------------- - -- Validate_Categorization_Dependency -- - ---------------------------------------- - - procedure Validate_Categorization_Dependency - (N : Node_Id; - E : Entity_Id) - is - K : constant Node_Kind := Nkind (N); - P : Node_Id := Parent (N); - U : Entity_Id := E; - Is_Subunit : constant Boolean := Nkind (P) = N_Subunit; - - begin - -- Only validate library units and subunits. For subunits, checks - -- concerning withed units apply to the parent compilation unit. - - if Is_Subunit then - P := Parent (P); - U := Scope (E); - - while Present (U) - and then not Is_Compilation_Unit (U) - and then not Is_Child_Unit (U) - loop - U := Scope (U); - end loop; - end if; - - if Nkind (P) /= N_Compilation_Unit then - return; - end if; - - -- Body of RCI unit does not need validation - - if Is_Remote_Call_Interface (E) - and then (Nkind (N) = N_Package_Body - or else Nkind (N) = N_Subprogram_Body) - then - return; - end if; - - -- Ada 2005 (AI-50217): Process explicit non-limited with_clauses - - declare - Item : Node_Id; - Entity_Of_Withed : Entity_Id; - - begin - Item := First (Context_Items (P)); - while Present (Item) loop - if Nkind (Item) = N_With_Clause - and then not (Implicit_With (Item) - or else Limited_Present (Item)) - then - Entity_Of_Withed := Entity (Name (Item)); - Check_Categorization_Dependencies - (U, Entity_Of_Withed, Item, Is_Subunit); - end if; - - Next (Item); - end loop; - end; - - -- Child depends on parent; therefore parent should also be categorized - -- and satisfy the dependency hierarchy. - - -- Check if N is a child spec - - if (K in N_Generic_Declaration or else - K in N_Generic_Instantiation or else - K in N_Generic_Renaming_Declaration or else - K = N_Package_Declaration or else - K = N_Package_Renaming_Declaration or else - K = N_Subprogram_Declaration or else - K = N_Subprogram_Renaming_Declaration) - and then Present (Parent_Spec (N)) - then - Check_Categorization_Dependencies (E, Scope (E), N, False); - - -- Verify that public child of an RCI library unit must also be an - -- RCI library unit (RM E.2.3(15)). - - if Is_Remote_Call_Interface (Scope (E)) - and then not Private_Present (P) - and then not Is_Remote_Call_Interface (E) - then - Error_Msg_N ("public child of rci unit must also be rci unit", N); - end if; - end if; - end Validate_Categorization_Dependency; - - -------------------------------- - -- Validate_Controlled_Object -- - -------------------------------- - - procedure Validate_Controlled_Object (E : Entity_Id) is - begin - -- Don't need this check in Ada 2005 mode, where this is all taken - -- care of by the mechanism for Preelaborable Initialization. - - if Ada_Version >= Ada_05 then - return; - end if; - - -- For now, never apply this check for internal GNAT units, since we - -- have a number of cases in the library where we are stuck with objects - -- of this type, and the RM requires Preelaborate. - - -- For similar reasons, we only do this check for source entities, since - -- we generate entities of this type in some situations. - - -- Note that the 10.2.1(9) restrictions are not relevant to us anyway. - -- We have to enforce them for RM compatibility, but we have no trouble - -- accepting these objects and doing the right thing. Note that there is - -- no requirement that Preelaborate not actually generate any code! - - if In_Preelaborated_Unit - and then not Debug_Flag_PP - and then Comes_From_Source (E) - and then not - Is_Internal_File_Name (Unit_File_Name (Get_Source_Unit (E))) - and then (not Inside_A_Generic - or else Present (Enclosing_Generic_Body (E))) - and then not Is_Protected_Type (Etype (E)) - then - Error_Msg_N - ("library level controlled object not allowed in " & - "preelaborated unit", E); - end if; - end Validate_Controlled_Object; - - -------------------------------------- - -- Validate_Null_Statement_Sequence -- - -------------------------------------- - - procedure Validate_Null_Statement_Sequence (N : Node_Id) is - Item : Node_Id; - - begin - if In_Preelaborated_Unit then - Item := First (Statements (Handled_Statement_Sequence (N))); - while Present (Item) loop - if Nkind (Item) /= N_Label - and then Nkind (Item) /= N_Null_Statement - then - -- In GNAT mode, this is a warning, allowing the run-time - -- to judiciously bypass this error condition. - - Error_Msg_Warn := GNAT_Mode; - Error_Msg_N - ("<statements not allowed in preelaborated unit", Item); - - exit; - end if; - - Next (Item); - end loop; - end if; - end Validate_Null_Statement_Sequence; - - --------------------------------- - -- Validate_Object_Declaration -- - --------------------------------- - - procedure Validate_Object_Declaration (N : Node_Id) is - Id : constant Entity_Id := Defining_Identifier (N); - E : constant Node_Id := Expression (N); - Odf : constant Node_Id := Object_Definition (N); - T : constant Entity_Id := Etype (Id); - - begin - -- Verify that any access to subprogram object does not have in its - -- subprogram profile access type parameters or limited parameters - -- without Read and Write attributes (E.2.3(13)). - - Validate_RCI_Subprogram_Declaration (N); - - -- Check that if we are in preelaborated elaboration code, then we - -- do not have an instance of a default initialized private, task or - -- protected object declaration which would violate (RM 10.2.1(9)). - -- Note that constants are never default initialized (and the test - -- below also filters out deferred constants). A variable is default - -- initialized if it does *not* have an initialization expression. - - -- Filter out cases that are not declaration of a variable from source - - if Nkind (N) /= N_Object_Declaration - or else Constant_Present (N) - or else not Comes_From_Source (Id) - then - return; - end if; - - -- Exclude generic specs from the checks (this will get rechecked - -- on instantiations). - - if Inside_A_Generic - and then No (Enclosing_Generic_Body (Id)) - then - return; - end if; - - -- Required checks for declaration that is in a preelaborated - -- package and is not within some subprogram. - - if In_Preelaborated_Unit - and then not In_Subprogram_Or_Concurrent_Unit - then - -- Check for default initialized variable case. Note that in - -- accordance with (RM B.1(24)) imported objects are not - -- subject to default initialization. - -- If the initialization does not come from source and is an - -- aggregate, it is a static initialization that replaces an - -- implicit call, and must be treated as such. - - if Present (E) - and then - (Comes_From_Source (E) or else Nkind (E) /= N_Aggregate) - then - null; - - elsif Is_Imported (Id) then - null; - - else - declare - Ent : Entity_Id := T; - - begin - -- An array whose component type is a record with nonstatic - -- default expressions is a violation, so we get the array's - -- component type. - - if Is_Array_Type (Ent) then - declare - Comp_Type : Entity_Id; - - begin - Comp_Type := Component_Type (Ent); - while Is_Array_Type (Comp_Type) loop - Comp_Type := Component_Type (Comp_Type); - end loop; - - Ent := Comp_Type; - end; - end if; - - -- Object decl. that is of record type and has no default expr. - -- should check if there is any non-static default expression - -- in component decl. of the record type decl. - - if Is_Record_Type (Ent) then - if Nkind (Parent (Ent)) = N_Full_Type_Declaration then - Check_Non_Static_Default_Expr - (Type_Definition (Parent (Ent)), N); - - elsif Nkind (Odf) = N_Subtype_Indication - and then not Is_Array_Type (T) - and then not Is_Private_Type (T) - then - Check_Non_Static_Default_Expr (Type_Definition - (Parent (Entity (Subtype_Mark (Odf)))), N); - end if; - end if; - - -- Check for invalid use of private object. Note that Ada 2005 - -- AI-161 modifies the rules for Ada 2005, including the use of - -- the new pragma Preelaborable_Initialization. - - if Is_Private_Type (Ent) - or else Depends_On_Private (Ent) - then - -- Case where type has preelaborable initialization which - -- means that a pragma Preelaborable_Initialization was - -- given for the private type. - - if Has_Preelaborable_Initialization (Ent) then - - -- But for the predefined units, we will ignore this - -- status unless we are in Ada 2005 mode since we want - -- Ada 95 compatible behavior, in which the entities - -- marked with this pragma in the predefined library are - -- not treated specially. - - if Ada_Version < Ada_05 then - Error_Msg_N - ("private object not allowed in preelaborated unit", - N); - Error_Msg_N ("\(would be legal in Ada 2005 mode)", N); - end if; - - -- Type does not have preelaborable initialization - - else - -- We allow this when compiling in GNAT mode to make life - -- easier for some cases where it would otherwise be hard - -- to be exactly valid Ada. - - if not GNAT_Mode then - Error_Msg_N - ("private object not allowed in preelaborated unit", - N); - - -- Add a message if it would help to provide a pragma - -- Preelaborable_Initialization on the type of the - -- object (which would make it legal in Ada 2005). - - -- If the type has no full view (generic type, or - -- previous error), the warning does not apply. - - if Is_Private_Type (Ent) - and then Present (Full_View (Ent)) - and then - Has_Preelaborable_Initialization (Full_View (Ent)) - then - Error_Msg_Sloc := Sloc (Ent); - - if Ada_Version >= Ada_05 then - Error_Msg_NE - ("\would be legal if pragma Preelaborable_" & - "Initialization given for & #", N, Ent); - else - Error_Msg_NE - ("\would be legal in Ada 2005 if pragma " & - "Preelaborable_Initialization given for & #", - N, Ent); - end if; - end if; - end if; - end if; - - -- Access to Task or Protected type - - elsif Is_Entity_Name (Odf) - and then Present (Etype (Odf)) - and then Is_Access_Type (Etype (Odf)) - then - Ent := Designated_Type (Etype (Odf)); - - elsif Is_Entity_Name (Odf) then - Ent := Entity (Odf); - - elsif Nkind (Odf) = N_Subtype_Indication then - Ent := Etype (Subtype_Mark (Odf)); - - elsif - Nkind (Odf) = N_Constrained_Array_Definition - then - Ent := Component_Type (T); - - -- else - -- return; - end if; - - if Is_Task_Type (Ent) - or else (Is_Protected_Type (Ent) and then Has_Entries (Ent)) - then - Error_Msg_N - ("concurrent object not allowed in preelaborated unit", - N); - return; - end if; - end; - end if; - - -- Non-static discriminant not allowed in preelaborated unit - -- Controlled object of a type with a user-defined Initialize - -- is forbidden as well. - - if Is_Record_Type (Etype (Id)) then - declare - ET : constant Entity_Id := Etype (Id); - EE : constant Entity_Id := Etype (Etype (Id)); - PEE : Node_Id; - - begin - if Has_Discriminants (ET) - and then Present (EE) - then - PEE := Parent (EE); - - if Nkind (PEE) = N_Full_Type_Declaration - and then not Static_Discriminant_Expr - (Discriminant_Specifications (PEE)) - then - Error_Msg_N - ("non-static discriminant in preelaborated unit", - PEE); - end if; - end if; - - if Has_Overriding_Initialize (ET) then - Error_Msg_NE - ("controlled type& does not have" - & " preelaborable initialization", N, ET); - end if; - end; - - end if; - end if; - - -- A pure library_item must not contain the declaration of any variable - -- except within a subprogram, generic subprogram, task unit, or - -- protected unit (RM 10.2.1(16)). - - if In_Pure_Unit - and then not In_Subprogram_Task_Protected_Unit - then - Error_Msg_N ("declaration of variable not allowed in pure unit", N); - - -- The visible part of an RCI library unit must not contain the - -- declaration of a variable (RM E.1.3(9)) - - elsif In_RCI_Declaration (N) then - Error_Msg_N ("declaration of variable not allowed in rci unit", N); - - -- The visible part of a Shared Passive library unit must not contain - -- the declaration of a variable (RM E.2.2(7)) - - elsif In_RT_Declaration then - Error_Msg_N - ("variable declaration not allowed in remote types unit", N); - end if; - - end Validate_Object_Declaration; - - ------------------------------ - -- Validate_RACW_Primitives -- - ------------------------------ - - procedure Validate_RACW_Primitives (T : Entity_Id) is - Desig_Type : Entity_Id; - Primitive_Subprograms : Elist_Id; - Subprogram_Elmt : Elmt_Id; - Subprogram : Entity_Id; - Param_Spec : Node_Id; - Param : Entity_Id; - Param_Type : Entity_Id; - Rtyp : Node_Id; - - procedure Illegal_RACW (Msg : String; N : Node_Id); - -- Diagnose that T is illegal because of the given reason, associated - -- with the location of node N. - - Illegal_RACW_Message_Issued : Boolean := False; - -- Set True once Illegal_RACW has been called - - ------------------ - -- Illegal_RACW -- - ------------------ - - procedure Illegal_RACW (Msg : String; N : Node_Id) is - begin - if not Illegal_RACW_Message_Issued then - Error_Msg_N - ("illegal remote access to class-wide type&", T); - Illegal_RACW_Message_Issued := True; - end if; - - Error_Msg_Sloc := Sloc (N); - Error_Msg_N ("\\" & Msg & " in primitive#", T); - end Illegal_RACW; - - -- Start of processing for Validate_RACW_Primitives - - begin - Desig_Type := Etype (Designated_Type (T)); - - Primitive_Subprograms := Primitive_Operations (Desig_Type); - - Subprogram_Elmt := First_Elmt (Primitive_Subprograms); - while Subprogram_Elmt /= No_Elmt loop - Subprogram := Node (Subprogram_Elmt); - - if Is_Predefined_Dispatching_Operation (Subprogram) - or else Is_Hidden (Subprogram) - then - goto Next_Subprogram; - end if; - - -- Check return type - - if Ekind (Subprogram) = E_Function then - Rtyp := Etype (Subprogram); - - if Has_Controlling_Result (Subprogram) then - null; - - elsif Ekind (Rtyp) = E_Anonymous_Access_Type then - Illegal_RACW ("anonymous access result", Rtyp); - - elsif Is_Limited_Type (Rtyp) then - if No (TSS (Rtyp, TSS_Stream_Read)) - or else - No (TSS (Rtyp, TSS_Stream_Write)) - then - Illegal_RACW - ("limited return type must have Read and Write attributes", - Parent (Subprogram)); - Explain_Limited_Type (Rtyp, Parent (Subprogram)); - - -- Check that the return type supports external streaming. - -- Note that the language of the standard (E.2.2(14)) does not - -- explicitly mention that case, but it really does not make - -- sense to return a value containing a local access type. - - elsif Missing_Read_Write_Attributes (Rtyp) - and then not Error_Posted (Rtyp) - then - Illegal_RACW ("return type containing non-remote access " - & "must have Read and Write attributes", - Parent (Subprogram)); - end if; - - end if; - end if; - - Param := First_Formal (Subprogram); - while Present (Param) loop - - -- Now find out if this parameter is a controlling parameter - - Param_Spec := Parent (Param); - Param_Type := Etype (Param); - - if Is_Controlling_Formal (Param) then - - -- It is a controlling parameter, so specific checks below - -- do not apply. - - null; - - elsif Ekind (Param_Type) = E_Anonymous_Access_Type - or else Ekind (Param_Type) = E_Anonymous_Access_Subprogram_Type - then - -- From RM E.2.2(14), no anonymous access parameter other than - -- controlling ones may be used (because an anonymous access - -- type never supports external streaming). - - Illegal_RACW ("non-controlling access parameter", Param_Spec); - - elsif Is_Limited_Type (Param_Type) then - - -- Not a controlling parameter, so type must have Read and - -- Write attributes. - - if No (TSS (Param_Type, TSS_Stream_Read)) - or else - No (TSS (Param_Type, TSS_Stream_Write)) - then - Illegal_RACW - ("limited formal must have Read and Write attributes", - Param_Spec); - Explain_Limited_Type (Param_Type, Param_Spec); - end if; - - elsif Missing_Read_Write_Attributes (Param_Type) - and then not Error_Posted (Param_Type) - then - Illegal_RACW ("parameter containing non-remote access " - & "must have Read and Write attributes", Param_Spec); - end if; - - -- Check next parameter in this subprogram - - Next_Formal (Param); - end loop; - - <<Next_Subprogram>> - Next_Elmt (Subprogram_Elmt); - end loop; - end Validate_RACW_Primitives; - - ------------------------------- - -- Validate_RCI_Declarations -- - ------------------------------- - - procedure Validate_RCI_Declarations (P : Entity_Id) is - E : Entity_Id; - - begin - E := First_Entity (P); - while Present (E) loop - if Comes_From_Source (E) then - if Is_Limited_Type (E) then - Error_Msg_N - ("limited type not allowed in rci unit", Parent (E)); - Explain_Limited_Type (E, Parent (E)); - - elsif Ekind (E) = E_Generic_Function - or else Ekind (E) = E_Generic_Package - or else Ekind (E) = E_Generic_Procedure - then - Error_Msg_N ("generic declaration not allowed in rci unit", - Parent (E)); - - elsif (Ekind (E) = E_Function - or else Ekind (E) = E_Procedure) - and then Has_Pragma_Inline (E) - then - Error_Msg_N - ("inlined subprogram not allowed in rci unit", Parent (E)); - - -- Inner packages that are renamings need not be checked. Generic - -- RCI packages are subject to the checks, but entities that come - -- from formal packages are not part of the visible declarations - -- of the package and are not checked. - - elsif Ekind (E) = E_Package then - if Present (Renamed_Entity (E)) then - null; - - elsif Ekind (P) /= E_Generic_Package - or else List_Containing (Unit_Declaration_Node (E)) /= - Generic_Formal_Declarations - (Unit_Declaration_Node (P)) - then - Validate_RCI_Declarations (E); - end if; - end if; - end if; - - Next_Entity (E); - end loop; - end Validate_RCI_Declarations; - - ----------------------------------------- - -- Validate_RCI_Subprogram_Declaration -- - ----------------------------------------- - - procedure Validate_RCI_Subprogram_Declaration (N : Node_Id) is - K : constant Node_Kind := Nkind (N); - Profile : List_Id; - Id : Node_Id; - Param_Spec : Node_Id; - Param_Type : Entity_Id; - Base_Param_Type : Entity_Id; - Base_Under_Type : Entity_Id; - Type_Decl : Node_Id; - Error_Node : Node_Id := N; - - begin - -- This procedure enforces rules on subprogram and access to subprogram - -- declarations in RCI units. These rules do not apply to expander - -- generated routines, which are not remote subprograms. It is called: - - -- 1. from Analyze_Subprogram_Declaration. - -- 2. from Validate_Object_Declaration (access to subprogram). - - if not (Comes_From_Source (N) and then In_RCI_Declaration (N)) then - return; - end if; - - if K = N_Subprogram_Declaration then - Profile := Parameter_Specifications (Specification (N)); - - else pragma Assert (K = N_Object_Declaration); - - -- The above assertion is dubious, the visible declarations of an - -- RCI unit never contain an object declaration, this should be an - -- ACCESS-to-object declaration??? - - Id := Defining_Identifier (N); - - if Nkind (Id) = N_Defining_Identifier - and then Nkind (Parent (Etype (Id))) = N_Full_Type_Declaration - and then Ekind (Etype (Id)) = E_Access_Subprogram_Type - then - Profile := - Parameter_Specifications (Type_Definition (Parent (Etype (Id)))); - else - return; - end if; - end if; - - -- Iterate through the parameter specification list, checking that - -- no access parameter and no limited type parameter in the list. - -- RM E.2.3(14). - - if Present (Profile) then - Param_Spec := First (Profile); - while Present (Param_Spec) loop - Param_Type := Etype (Defining_Identifier (Param_Spec)); - Type_Decl := Parent (Param_Type); - - if Ekind (Param_Type) = E_Anonymous_Access_Type then - - if K = N_Subprogram_Declaration then - Error_Node := Param_Spec; - end if; - - -- Report error only if declaration is in source program - - if Comes_From_Source - (Defining_Entity (Specification (N))) - then - Error_Msg_N - ("subprogram in 'R'C'I unit cannot have access parameter", - Error_Node); - end if; - - -- For a limited private type parameter, we check only the private - -- declaration and ignore full type declaration, unless this is - -- the only declaration for the type, e.g., as a limited record. - - elsif Is_Limited_Type (Param_Type) - and then (Nkind (Type_Decl) = N_Private_Type_Declaration - or else - (Nkind (Type_Decl) = N_Full_Type_Declaration - and then not (Has_Private_Declaration (Param_Type)) - and then Comes_From_Source (N))) - then - -- A limited parameter is legal only if user-specified Read and - -- Write attributes exist for it. Second part of RM E.2.3 (14). - - if No (Full_View (Param_Type)) - and then Ekind (Param_Type) /= E_Record_Type - then - -- Type does not have completion yet, so if declared in - -- the current RCI scope it is illegal, and will be flagged - -- subsequently. - - return; - end if; - - -- In Ada 95 the rules permit using a limited type that has - -- user-specified Read and Write attributes that are specified - -- in the private part of the package, whereas Ada 2005 - -- (AI-240) revises this to require the attributes to be - -- "available" (implying that the attribute clauses must be - -- visible to the RCI client). The Ada 95 rules violate the - -- contract model for privacy, but we support both semantics - -- for now for compatibility (note that ACATS test BXE2009 - -- checks a case that conforms to the Ada 95 rules but is - -- illegal in Ada 2005). In the Ada 2005 case we check for the - -- possibilities of visible TSS stream subprograms or explicit - -- stream attribute definitions because the TSS subprograms - -- can be hidden in the private part while the attribute - -- definitions are still be available from the visible part. - - Base_Param_Type := Base_Type (Param_Type); - Base_Under_Type := Base_Type (Underlying_Type - (Base_Param_Type)); - - if (Ada_Version < Ada_05 - and then - (No (TSS (Base_Param_Type, TSS_Stream_Read)) - or else - No (TSS (Base_Param_Type, TSS_Stream_Write))) - and then - (No (TSS (Base_Under_Type, TSS_Stream_Read)) - or else - No (TSS (Base_Under_Type, TSS_Stream_Write)))) - or else - (Ada_Version >= Ada_05 - and then - (No (TSS (Base_Param_Type, TSS_Stream_Read)) - or else - No (TSS (Base_Param_Type, TSS_Stream_Write)) - or else - Is_Hidden (TSS (Base_Param_Type, TSS_Stream_Read)) - or else - Is_Hidden (TSS (Base_Param_Type, TSS_Stream_Write))) - and then - (not Has_Stream_Attribute_Definition - (Base_Param_Type, TSS_Stream_Read) - or else - not Has_Stream_Attribute_Definition - (Base_Param_Type, TSS_Stream_Write))) - then - if K = N_Subprogram_Declaration then - Error_Node := Param_Spec; - end if; - - if Ada_Version >= Ada_05 then - Error_Msg_N - ("limited parameter in 'R'C'I unit " - & "must have visible read/write attributes ", - Error_Node); - else - Error_Msg_N - ("limited parameter in 'R'C'I unit " - & "must have read/write attributes ", - Error_Node); - end if; - Explain_Limited_Type (Param_Type, Error_Node); - end if; - - -- In Ada 95, any non-remote access type (or any type with a - -- component of a non-remote access type) that is visible in an - -- RCI unit comes from a Remote_Types or Remote_Call_Interface - -- unit, and thus is already guaranteed to support external - -- streaming. However in Ada 2005 we have to account for the case - -- of named access types from declared pure units as well, which - -- may or may not support external streaming, and so we need to - -- perform a specific check for E.2.3(14/2) here. - - -- Note that if the declaration of the type itself is illegal, we - -- do not perform this check since it might be a cascaded error. - - else - if K = N_Subprogram_Declaration then - Error_Node := Param_Spec; - end if; - - if Missing_Read_Write_Attributes (Param_Type) - and then not Error_Posted (Param_Type) - then - Error_Msg_N - ("parameter containing non-remote access in 'R'C'I " - & "subprogram must have visible " - & "Read and Write attributes", Error_Node); - end if; - end if; - Next (Param_Spec); - end loop; - - -- No check on return type??? - end if; - end Validate_RCI_Subprogram_Declaration; - - ---------------------------------------------------- - -- Validate_Remote_Access_Object_Type_Declaration -- - ---------------------------------------------------- - - procedure Validate_Remote_Access_Object_Type_Declaration (T : Entity_Id) is - - function Is_Valid_Remote_Object_Type (E : Entity_Id) return Boolean; - -- True if tagged type E is a valid candidate as the root type of the - -- designated type for a RACW, i.e. a tagged limited private type, or a - -- limited interface type, or a private extension of such a type. - - --------------------------------- - -- Is_Valid_Remote_Object_Type -- - --------------------------------- - - function Is_Valid_Remote_Object_Type (E : Entity_Id) return Boolean is - P : constant Node_Id := Parent (E); - - begin - pragma Assert (Is_Tagged_Type (E)); - - -- Simple case: a limited private type - - if Nkind (P) = N_Private_Type_Declaration - and then Is_Limited_Record (E) - then - return True; - - -- A limited interface is not currently a legal ancestor for the - -- designated type of an RACW type, because a type that implements - -- such an interface need not be limited. However, the ARG seems to - -- incline towards allowing an access to classwide limited interface - -- type as a remote access type, as resolved in AI05-060. But note - -- that the expansion circuitry for RACWs that designate classwide - -- interfaces is not complete yet. - - elsif Is_Limited_Record (E) and then Is_Limited_Interface (E) then - return True; - - -- A generic tagged limited type is a valid candidate. Limitedness - -- will be checked again on the actual at instantiation point. - - elsif Nkind (P) = N_Formal_Type_Declaration - and then Ekind (E) = E_Record_Type_With_Private - and then Is_Generic_Type (E) - and then Is_Limited_Record (E) - then - return True; - - -- A private extension declaration is a valid candidate if its parent - -- type is. - - elsif Nkind (P) = N_Private_Extension_Declaration then - return Is_Valid_Remote_Object_Type (Etype (E)); - - else - return False; - end if; - end Is_Valid_Remote_Object_Type; - - -- Local variables - - Direct_Designated_Type : Entity_Id; - Desig_Type : Entity_Id; - - -- Start of processing for Validate_Remote_Access_Object_Type_Declaration - - begin - -- We are called from Analyze_Type_Declaration, and the Nkind of the - -- given node is N_Access_To_Object_Definition. - - if not Comes_From_Source (T) - or else (not In_RCI_Declaration (Parent (T)) - and then not In_RT_Declaration) - then - return; - end if; - - -- An access definition in the private part of a Remote Types package - -- may be legal if it has user-defined Read and Write attributes. This - -- will be checked at the end of the package spec processing. - - if In_RT_Declaration and then In_Private_Part (Scope (T)) then - return; - end if; - - -- Check RCI or RT unit type declaration. It may not contain the - -- declaration of an access-to-object type unless it is a general access - -- type that designates a class-wide limited private type. There are - -- also constraints on the primitive subprograms of the class-wide type - -- (RM E.2.2(14), see Validate_RACW_Primitives). - - if Ekind (T) /= E_General_Access_Type - or else Ekind (Designated_Type (T)) /= E_Class_Wide_Type - then - if In_RCI_Declaration (Parent (T)) then - Error_Msg_N - ("error in access type in Remote_Call_Interface unit", T); - else - Error_Msg_N - ("error in access type in Remote_Types unit", T); - end if; - - Error_Msg_N ("\must be general access to class-wide type", T); - return; - end if; - - Direct_Designated_Type := Designated_Type (T); - Desig_Type := Etype (Direct_Designated_Type); - - -- Why is the check below not in - -- Validate_Remote_Access_To_Class_Wide_Type??? - - if not Is_Valid_Remote_Object_Type (Desig_Type) then - Error_Msg_N - ("error in designated type of remote access to class-wide type", T); - Error_Msg_N - ("\must be tagged limited private or private extension", T); - return; - end if; - end Validate_Remote_Access_Object_Type_Declaration; - - ----------------------------------------------- - -- Validate_Remote_Access_To_Class_Wide_Type -- - ----------------------------------------------- - - procedure Validate_Remote_Access_To_Class_Wide_Type (N : Node_Id) is - K : constant Node_Kind := Nkind (N); - PK : constant Node_Kind := Nkind (Parent (N)); - E : Entity_Id; - - begin - -- This subprogram enforces the checks in (RM E.2.2(8)) for certain uses - -- of class-wide limited private types. - - -- Storage_Pool and Storage_Size are not defined for such types - -- - -- The expected type of allocator must not be such a type. - - -- The actual parameter of generic instantiation must not be such a - -- type if the formal parameter is of an access type. - - -- On entry, there are five cases - - -- 1. called from sem_attr Analyze_Attribute where attribute name is - -- either Storage_Pool or Storage_Size. - - -- 2. called from exp_ch4 Expand_N_Allocator - - -- 3. called from sem_ch12 Analyze_Associations - - -- 4. called from sem_ch4 Analyze_Explicit_Dereference - - -- 5. called from sem_res Resolve_Actuals - - if K = N_Attribute_Reference then - E := Etype (Prefix (N)); - - if Is_Remote_Access_To_Class_Wide_Type (E) then - Error_Msg_N ("incorrect attribute of remote operand", N); - return; - end if; - - elsif K = N_Allocator then - E := Etype (N); - - if Is_Remote_Access_To_Class_Wide_Type (E) then - Error_Msg_N ("incorrect expected remote type of allocator", N); - return; - end if; - - elsif K in N_Has_Entity then - E := Entity (N); - - if Is_Remote_Access_To_Class_Wide_Type (E) then - Error_Msg_N ("incorrect remote type generic actual", N); - return; - end if; - - -- This subprogram also enforces the checks in E.2.2(13). A value of - -- such type must not be dereferenced unless as controlling operand of - -- a dispatching call. Explicit dereferences not coming from source are - -- exempted from this checking because the expander produces them in - -- some cases (such as for tag checks on dispatching calls with multiple - -- controlling operands). However we do check in the case of an implicit - -- dereference that is expanded to an explicit dereference (hence the - -- test of whether Original_Node (N) comes from source). - - elsif K = N_Explicit_Dereference - and then Comes_From_Source (Original_Node (N)) - then - E := Etype (Prefix (N)); - - -- If the class-wide type is not a remote one, the restrictions - -- do not apply. - - if not Is_Remote_Access_To_Class_Wide_Type (E) then - return; - end if; - - -- If we have a true dereference that comes from source and that - -- is a controlling argument for a dispatching call, accept it. - - if Is_Actual_Parameter (N) - and then Is_Controlling_Actual (N) - then - return; - end if; - - -- If we are just within a procedure or function call and the - -- dereference has not been analyzed, return because this procedure - -- will be called again from sem_res Resolve_Actuals. The same can - -- apply in the case of dereference that is the prefix of a selected - -- component, which can be a call given in prefixed form. - - if (Is_Actual_Parameter (N) - or else PK = N_Selected_Component) - and then not Analyzed (N) - then - return; - end if; - - -- We must allow expanded code to generate a reference to the tag of - -- the designated object (may be either the actual tag, or the stub - -- tag in the case of a remote object). - - if PK = N_Selected_Component - and then Is_Tag (Entity (Selector_Name (Parent (N)))) - then - return; - end if; - - Error_Msg_N - ("invalid dereference of a remote access-to-class-wide value", N); - end if; - end Validate_Remote_Access_To_Class_Wide_Type; - - ------------------------------------------ - -- Validate_Remote_Type_Type_Conversion -- - ------------------------------------------ - - procedure Validate_Remote_Type_Type_Conversion (N : Node_Id) is - S : constant Entity_Id := Etype (N); - E : constant Entity_Id := Etype (Expression (N)); - - begin - -- This test is required in the case where a conversion appears inside a - -- normal package, it does not necessarily have to be inside an RCI, - -- Remote_Types unit (RM E.2.2(9,12)). - - if Is_Remote_Access_To_Subprogram_Type (E) - and then not Is_Remote_Access_To_Subprogram_Type (S) - then - Error_Msg_N - ("incorrect conversion of remote operand to local type", N); - return; - - elsif not Is_Remote_Access_To_Subprogram_Type (E) - and then Is_Remote_Access_To_Subprogram_Type (S) - then - Error_Msg_N - ("incorrect conversion of local operand to remote type", N); - return; - - elsif Is_Remote_Access_To_Class_Wide_Type (E) - and then not Is_Remote_Access_To_Class_Wide_Type (S) - then - Error_Msg_N - ("incorrect conversion of remote operand to local type", N); - return; - end if; - - -- If a local access type is converted into a RACW type, then the - -- current unit has a pointer that may now be exported to another - -- partition. - - if Is_Remote_Access_To_Class_Wide_Type (S) - and then not Is_Remote_Access_To_Class_Wide_Type (E) - then - Set_Has_RACW (Current_Sem_Unit); - end if; - end Validate_Remote_Type_Type_Conversion; - - ------------------------------- - -- Validate_RT_RAT_Component -- - ------------------------------- - - procedure Validate_RT_RAT_Component (N : Node_Id) is - Spec : constant Node_Id := Specification (N); - Name_U : constant Entity_Id := Defining_Entity (Spec); - Typ : Entity_Id; - U_Typ : Entity_Id; - First_Priv_Ent : constant Entity_Id := First_Private_Entity (Name_U); - - begin - if not Is_Remote_Types (Name_U) then - return; - end if; - - Typ := First_Entity (Name_U); - while Present (Typ) and then Typ /= First_Priv_Ent loop - U_Typ := Underlying_Type (Typ); - - if No (U_Typ) then - U_Typ := Typ; - end if; - - if Comes_From_Source (Typ) and then Is_Type (Typ) then - if Missing_Read_Write_Attributes (Typ) then - if Is_Non_Remote_Access_Type (Typ) then - Error_Msg_N ("error in non-remote access type", U_Typ); - else - Error_Msg_N - ("error in record type containing a component of a " & - "non-remote access type", U_Typ); - end if; - - if Ada_Version >= Ada_05 then - Error_Msg_N - ("\must have visible Read and Write attribute " & - "definition clauses (RM E.2.2(8))", U_Typ); - else - Error_Msg_N - ("\must have Read and Write attribute " & - "definition clauses (RM E.2.2(8))", U_Typ); - end if; - end if; - end if; - - Next_Entity (Typ); - end loop; - end Validate_RT_RAT_Component; - - ----------------------------------------- - -- Validate_SP_Access_Object_Type_Decl -- - ----------------------------------------- - - procedure Validate_SP_Access_Object_Type_Decl (T : Entity_Id) is - Direct_Designated_Type : Entity_Id; - - function Has_Entry_Declarations (E : Entity_Id) return Boolean; - -- Return true if the protected type designated by T has - -- entry declarations. - - ---------------------------- - -- Has_Entry_Declarations -- - ---------------------------- - - function Has_Entry_Declarations (E : Entity_Id) return Boolean is - Ety : Entity_Id; - - begin - if Nkind (Parent (E)) = N_Protected_Type_Declaration then - Ety := First_Entity (E); - while Present (Ety) loop - if Ekind (Ety) = E_Entry then - return True; - end if; - - Next_Entity (Ety); - end loop; - end if; - - return False; - end Has_Entry_Declarations; - - -- Start of processing for Validate_SP_Access_Object_Type_Decl - - begin - -- We are called from Sem_Ch3.Analyze_Type_Declaration, and the - -- Nkind of the given entity is N_Access_To_Object_Definition. - - if not Comes_From_Source (T) - or else not In_Shared_Passive_Unit - or else In_Subprogram_Task_Protected_Unit - then - return; - end if; - - -- Check Shared Passive unit. It should not contain the declaration - -- of an access-to-object type whose designated type is a class-wide - -- type, task type or protected type with entry (RM E.2.1(7)). - - Direct_Designated_Type := Designated_Type (T); - - if Ekind (Direct_Designated_Type) = E_Class_Wide_Type then - Error_Msg_N - ("invalid access-to-class-wide type in shared passive unit", T); - return; - - elsif Ekind (Direct_Designated_Type) in Task_Kind then - Error_Msg_N - ("invalid access-to-task type in shared passive unit", T); - return; - - elsif Ekind (Direct_Designated_Type) in Protected_Kind - and then Has_Entry_Declarations (Direct_Designated_Type) - then - Error_Msg_N - ("invalid access-to-protected type in shared passive unit", T); - return; - end if; - end Validate_SP_Access_Object_Type_Decl; - - --------------------------------- - -- Validate_Static_Object_Name -- - --------------------------------- - - procedure Validate_Static_Object_Name (N : Node_Id) is - E : Entity_Id; - - function Is_Primary (N : Node_Id) return Boolean; - -- Determine whether node is syntactically a primary in an expression - -- This function should probably be somewhere else ??? - -- Also it does not do what it says, e.g if N is a binary operator - -- whose parent is a binary operator, Is_Primary returns True ??? - - ---------------- - -- Is_Primary -- - ---------------- - - function Is_Primary (N : Node_Id) return Boolean is - K : constant Node_Kind := Nkind (Parent (N)); - - begin - case K is - when N_Op | N_Membership_Test => - return True; - - when N_Aggregate - | N_Component_Association - | N_Index_Or_Discriminant_Constraint => - return True; - - when N_Attribute_Reference => - return Attribute_Name (Parent (N)) /= Name_Address - and then Attribute_Name (Parent (N)) /= Name_Access - and then Attribute_Name (Parent (N)) /= Name_Unchecked_Access - and then - Attribute_Name (Parent (N)) /= Name_Unrestricted_Access; - - when N_Indexed_Component => - return (N /= Prefix (Parent (N)) - or else Is_Primary (Parent (N))); - - when N_Qualified_Expression | N_Type_Conversion => - return Is_Primary (Parent (N)); - - when N_Assignment_Statement | N_Object_Declaration => - return (N = Expression (Parent (N))); - - when N_Selected_Component => - return Is_Primary (Parent (N)); - - when others => - return False; - end case; - end Is_Primary; - - -- Start of processing for Validate_Static_Object_Name - - begin - if not In_Preelaborated_Unit - or else not Comes_From_Source (N) - or else In_Subprogram_Or_Concurrent_Unit - or else Ekind (Current_Scope) = E_Block - then - return; - - -- Filter out cases where primary is default in a component declaration, - -- discriminant specification, or actual in a record type initialization - -- call. - - -- Initialization call of internal types - - elsif Nkind (Parent (N)) = N_Procedure_Call_Statement then - - if Present (Parent (Parent (N))) - and then Nkind (Parent (Parent (N))) = N_Freeze_Entity - then - return; - end if; - - if Nkind (Name (Parent (N))) = N_Identifier - and then not Comes_From_Source (Entity (Name (Parent (N)))) - then - return; - end if; - end if; - - -- Error if the name is a primary in an expression. The parent must not - -- be an operator, or a selected component or an indexed component that - -- is itself a primary. Entities that are actuals do not need to be - -- checked, because the call itself will be diagnosed. - - if Is_Primary (N) - and then (not Inside_A_Generic - or else Present (Enclosing_Generic_Body (N))) - then - if Ekind (Entity (N)) = E_Variable - or else Ekind (Entity (N)) in Formal_Object_Kind - then - Flag_Non_Static_Expr - ("non-static object name in preelaborated unit", N); - - -- We take the view that a constant defined in another preelaborated - -- unit is preelaborable, even though it may have a private type and - -- thus appear non-static in a client. This must be the intent of - -- the language, but currently is an RM gap ??? - - elsif Ekind (Entity (N)) = E_Constant - and then not Is_Static_Expression (N) - then - E := Entity (N); - - if Is_Internal_File_Name (Unit_File_Name (Get_Source_Unit (N))) - and then - Enclosing_Lib_Unit_Node (N) /= Enclosing_Lib_Unit_Node (E) - and then (Is_Preelaborated (Scope (E)) - or else Is_Pure (Scope (E)) - or else (Present (Renamed_Object (E)) - and then - Is_Entity_Name (Renamed_Object (E)) - and then - (Is_Preelaborated - (Scope (Renamed_Object (E))) - or else - Is_Pure (Scope - (Renamed_Object (E)))))) - then - null; - - -- This is the error case - - else - -- In GNAT mode, this is just a warning, to allow it to be - -- judiciously turned off. Otherwise it is a real error. - - if GNAT_Mode then - Error_Msg_N - ("?non-static constant in preelaborated unit", N); - else - Flag_Non_Static_Expr - ("non-static constant in preelaborated unit", N); - end if; - end if; - end if; - end if; - end Validate_Static_Object_Name; - -end Sem_Cat; |