Mercurial > hg > CbC > CbC_gcc
view gcc/ada/sem_cat.adb @ 111:04ced10e8804
gcc 7
| author | kono |
|---|---|
| date | Fri, 27 Oct 2017 22:46:09 +0900 |
| parents | |
| children | 84e7813d76e9 |
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------------------------------------------------------------------------------ -- -- -- GNAT COMPILER COMPONENTS -- -- -- -- S E M _ C A T -- -- -- -- B o d y -- -- -- -- Copyright (C) 1992-2017, 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 Lib; use Lib; with Namet; use Namet; with Nlists; use Nlists; with Opt; use Opt; with Sem; use Sem; with Sem_Attr; use Sem_Attr; with Sem_Aux; use Sem_Aux; with Sem_Dist; use Sem_Dist; 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. 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. 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 Has_Non_Remote_Access (Typ : Entity_Id) return Boolean; -- Return true if Typ or the type of any of its subcomponents is a non -- remote access type and doesn't have user-defined stream attributes. function No_External_Streaming (E : Entity_Id) return Boolean; -- Return True if the entity or one of its subcomponents does not support -- external streaming. function In_RCI_Declaration return Boolean; function In_RT_Declaration return Boolean; -- Determine if current scope is within the declaration of a Remote Call -- Interface or Remote Types unit, for semantic checking purposes. function In_Package_Declaration return Boolean; -- Shared supporting routine for In_RCI_Declaration and In_RT_Declaration 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) procedure Validate_RACW_Primitive (Subp : Entity_Id; RACW : Entity_Id); -- Check legality of the declaration of primitive Subp of the designated -- type of the given RACW type. --------------------------------------- -- 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; Err : Boolean; -- 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. type Categorization is (Pure, Shared_Passive, Remote_Types, Remote_Call_Interface, 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; 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. Also, ignore categorization -- dependencies when compilation switch -gnatdu is used. if Is_Intrinsic_Subprogram (Depended_Entity) or else Debug_Flag_U then return; end if; -- First check 10.2.1 (11/1) rules on preelaborate packages if Is_Preelaborated (Unit_Entity) and then not Is_Preelaborated (Depended_Entity) and then not Is_Pure (Depended_Entity) then Err := True; else Err := False; end if; -- Check categorization rules of RM E.2(5) Unit_Category := Get_Categorization (Unit_Entity); With_Category := Get_Categorization (Depended_Entity); if With_Category > Unit_Category then -- Special case: Remote_Types and Remote_Call_Interface are allowed -- to WITH anything in the package body, per (RM E.2(5)). if (Unit_Category = Remote_Types or else Unit_Category = Remote_Call_Interface) and then In_Package_Body (Unit_Entity) then null; -- Special case: Remote_Types and Remote_Call_Interface declarations -- can depend on a preelaborated unit via a private with_clause, per -- AI05-0206. elsif (Unit_Category = Remote_Types or else Unit_Category = Remote_Call_Interface) and then Nkind (N) = N_With_Clause and then Private_Present (N) and then Is_Preelaborated (Depended_Entity) then null; -- All other cases, we do have an error else Err := True; end if; end if; -- Here if we have an error if Err then -- These messages are warnings in GNAT mode or if the -gnateP switch -- was set. Otherwise these are real errors for real illegalities. -- The reason we suppress these errors in GNAT mode is that the run- -- time has several instances of violations of the categorization -- errors (e.g. Pure units withing Preelaborate units. All these -- violations are harmless in the cases where we intend them, and -- we suppress the warnings with Warnings (Off). In cases where we -- do not intend the violation, warnings are errors in GNAT mode -- anyway, so we will still get an error. Error_Msg_Warn := Treat_Categorization_Errors_As_Warnings or GNAT_Mode; -- 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_Unit (Current_Sem_Unit) and then not Is_Internal_Unit (Main_Unit) then return; -- Dependence of Remote_Types or Remote_Call_Interface declaration -- on a preelaborated unit with a normal with_clause. elsif (Unit_Category = Remote_Types or else Unit_Category = Remote_Call_Interface) and then Is_Preelaborated (Depended_Entity) then Error_Msg_NE ("<<must use private with clause for preelaborated unit& ", N, Depended_Entity); -- 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 Pure/Preelaborate common cases if Unit_Category = Pure then Error_Msg_NE ("\<<pure unit cannot depend on non-pure unit", N, Depended_Entity); elsif Is_Preelaborated (Unit_Entity) and then not Is_Preelaborated (Depended_Entity) and then not Is_Pure (Depended_Entity) then Error_Msg_NE ("\<<preelaborated unit cannot depend on " & "non-preelaborated unit", N, Depended_Entity); 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_OK_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_Non_Remote_Access -- --------------------------- function Has_Non_Remote_Access (Typ : Entity_Id) return Boolean is Component : Entity_Id; Comp_Type : Entity_Id; U_Typ : constant Entity_Id := Underlying_Type (Typ); begin if No (U_Typ) then return False; elsif Has_Read_Write_Attributes (Typ) or else Has_Read_Write_Attributes (U_Typ) then return False; elsif Is_Non_Remote_Access_Type (U_Typ) then return True; end if; if Is_Record_Type (U_Typ) then Component := First_Entity (U_Typ); while Present (Component) loop if not Is_Tag (Component) then Comp_Type := Etype (Component); if Has_Non_Remote_Access (Comp_Type) then return True; end if; end if; Next_Entity (Component); end loop; elsif Is_Array_Type (U_Typ) then return Has_Non_Remote_Access (Component_Type (U_Typ)); end if; return False; end Has_Non_Remote_Access; ------------------------------- -- 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; ------------------------------------- -- 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; Real_Rep : Node_Id; -- The stream operation may be specified by an attribute definition -- clause in the source, or by an aspect that generates such an -- attribute definition. For an aspect, the generated attribute -- definition may be placed at the freeze point of the full view of -- the type, but the aspect specification makes the operation visible -- to a client wherever the partial view is visible. begin -- 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 (Typ); while Present (Rep_Item) loop Real_Rep := Rep_Item; -- If the representation item is an aspect specification, retrieve -- the corresponding pragma or attribute definition. if Nkind (Rep_Item) = N_Aspect_Specification then Real_Rep := Aspect_Rep_Item (Rep_Item); end if; if Nkind (Real_Rep) = N_Attribute_Definition_Clause then case Chars (Real_Rep) 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 not found, and the type is derived from a private view, check -- for a stream attribute inherited from parent. 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 No (Rep_Item) and then Is_Private_Type (Typ) and then Is_Derived_Type (Typ) and then Present (Full_View (Typ)) then return Has_Stream_Attribute_Definition (Underlying_Type (Typ), Nam, At_Any_Place); -- Otherwise, 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. else return Present (Rep_Item) and then (Ada_Version < Ada_2005 or else At_Any_Place or else not Is_Hidden (Entity (Rep_Item))); end if; end Has_Stream_Attribute_Definition; ---------------------------- -- In_Package_Declaration -- ---------------------------- function In_Package_Declaration return Boolean is Unit_Kind : constant Node_Kind := Nkind (Unit (Cunit (Current_Sem_Unit))); begin -- There are no restrictions on the body of an RCI or RT unit return Is_Package_Or_Generic_Package (Current_Scope) and then Unit_Kind /= N_Package_Body and then not In_Package_Body (Current_Scope) and then not In_Instance; end In_Package_Declaration; --------------------------- -- In_Preelaborated_Unit -- --------------------------- function In_Preelaborated_Unit return Boolean is Unit_Entity : Entity_Id := Current_Scope; Unit_Kind : constant Node_Kind := Nkind (Unit (Cunit (Current_Sem_Unit))); begin -- If evaluating actuals for a child unit instantiation, then ignore -- the preelaboration status of the parent; use the child instead. if Is_Compilation_Unit (Unit_Entity) and then Unit_Kind in N_Generic_Instantiation and then not In_Same_Source_Unit (Unit_Entity, Cunit (Current_Sem_Unit)) then Unit_Entity := Cunit_Entity (Current_Sem_Unit); end if; -- There are no constraints on the 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 return Boolean is begin return Is_Remote_Call_Interface (Current_Scope) and then In_Package_Declaration; end In_RCI_Declaration; ----------------------- -- In_RT_Declaration -- ----------------------- function In_RT_Declaration return Boolean is begin return Is_Remote_Types (Current_Scope) and then In_Package_Declaration; 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_Or_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 (Base_Type (E)); -- Use full view of base type to handle subtypes properly. 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; --------------------------- -- No_External_Streaming -- --------------------------- function No_External_Streaming (E : Entity_Id) return Boolean is U_E : constant Entity_Id := Underlying_Type (E); begin if No (U_E) then return False; elsif Has_Read_Write_Attributes (E) then -- Note: availability of stream attributes is tested on E, not U_E. -- There may be stream attributes defined on U_E that are not visible -- at the place where support of external streaming is tested. return False; elsif Has_Non_Remote_Access (U_E) then return True; end if; return Is_Limited_Type (E); end No_External_Streaming; ------------------------------------- -- 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 -- Do not modify the purity of an internally generated entity if it has -- been explicitly marked as pure for optimization purposes. if not Has_Pragma_Pure_Function (E) then Set_Is_Pure (E, Is_Pure (Scop) and then Is_Library_Level_Entity (E)); end if; if not Is_Remote_Call_Interface (E) then if Ekind (E) in Subprogram_Kind then Declaration := Unit_Declaration_Node (E); if Nkind_In (Declaration, N_Subprogram_Body, 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_OK_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_2005 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 Ada 95 weakness in this area ??? if Is_Private_Type (T) and then not Has_Pragma_Preelab_Init (T) and then not In_Internal_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_In (N, N_Package_Body, 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) -- Skip if error already posted on the WITH clause (in -- which case the Name attribute may be invalid). In -- particular, this fixes the problem of hanging in the -- presence of a WITH clause on a child that is an -- illegal generic instantiation. or else Error_Posted (Item)) and then not (Try_Semantics -- Skip processing malformed trees and then Nkind (Name (Item)) not in N_Has_Entity) 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_2005 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 In_Internal_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 Relaxed_RM_Semantics then -- In relaxed mode, do not issue these messages, this -- is basically similar to the GNAT_Mode test below. null; elsif 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_2005 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_2005 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); 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 discriminants not allowed in preelaborated unit. -- Objects of a controlled type with a user-defined Initialize -- are 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; -- For controlled type or type with controlled component, check -- preelaboration flag, as there may be a non-null Initialize -- primitive. For language versions earlier than Ada 2005, -- there is no notion of preelaborable initialization, and -- Validate_Controlled_Object is used to enforce rules for -- controlled objects. if (Is_Controlled (ET) or else Has_Controlled_Component (ET)) and then Ada_Version >= Ada_2005 and then not Has_Preelaborable_Initialization (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); elsif not In_Private_Part (Id) then -- The visible part of an RCI library unit must not contain the -- declaration of a variable (RM E.1.3(9)). if In_RCI_Declaration then Error_Msg_N ("visible variable not allowed in 'R'C'I 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 ("visible variable not allowed in remote types unit", N); end if; end if; end Validate_Object_Declaration; ----------------------------- -- Validate_RACW_Primitive -- ----------------------------- procedure Validate_RACW_Primitive (Subp : Entity_Id; RACW : Entity_Id) is procedure Illegal_Remote_Subp (Msg : String; N : Node_Id); -- Diagnose illegality on N. If RACW is present, report the error on it -- rather than on N. ------------------------- -- Illegal_Remote_Subp -- ------------------------- procedure Illegal_Remote_Subp (Msg : String; N : Node_Id) is begin if Present (RACW) then if not Error_Posted (RACW) then Error_Msg_N ("illegal remote access to class-wide type&", RACW); end if; Error_Msg_Sloc := Sloc (N); Error_Msg_NE ("\\" & Msg & " in primitive& #", RACW, Subp); else Error_Msg_NE (Msg & " in remote subprogram&", N, Subp); end if; end Illegal_Remote_Subp; Rtyp : Entity_Id; Param : Node_Id; Param_Spec : Node_Id; Param_Type : Entity_Id; -- Start of processing for Validate_RACW_Primitive begin -- Check return type if Ekind (Subp) = E_Function then Rtyp := Etype (Subp); -- AI05-0101 (Binding Interpretation): The result type of a remote -- function must either support external streaming or be a -- controlling access result type. if Has_Controlling_Result (Subp) then null; elsif Ekind (Rtyp) = E_Anonymous_Access_Type then Illegal_Remote_Subp ("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_Remote_Subp ("limited return type must have Read and Write attributes", Parent (Subp)); Explain_Limited_Type (Rtyp, Parent (Subp)); end if; -- Check that the return type supports external streaming elsif No_External_Streaming (Rtyp) and then not Error_Posted (Rtyp) then Illegal_Remote_Subp ("return type containing non-remote access " & "must have Read and Write attributes", Parent (Subp)); end if; end if; Param := First_Formal (Subp); 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_In (Param_Type, E_Anonymous_Access_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_Remote_Subp ("non-controlling access parameter", Param_Spec); elsif No_External_Streaming (Param_Type) and then not Error_Posted (Param_Type) then Illegal_Remote_Subp ("formal parameter in remote subprogram must " & "support external streaming", Param_Spec); end if; -- Check next parameter in this subprogram Next_Formal (Param); end loop; end Validate_RACW_Primitive; ------------------------------ -- 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; begin Desig_Type := Etype (Designated_Type (T)); -- No action needed for concurrent types if Is_Concurrent_Type (Desig_Type) then return; end if; 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; Validate_RACW_Primitive (Subp => Subprogram, RACW => T); <<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_In (E, E_Generic_Function, E_Generic_Package, 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 : constant Entity_Id := Defining_Entity (N); Param_Spec : Node_Id; Param_Type : Entity_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 and then not In_Private_Part (Scope (Id))) 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??? 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)); 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 (Id) 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 No_External_Streaming (Param_Type) then if K = N_Subprogram_Declaration then Error_Node := Param_Spec; end if; Error_Msg_NE ("formal of remote subprogram& " & "must support external streaming", Error_Node, Id); if Is_Limited_Type (Param_Type) then Explain_Limited_Type (Param_Type, Error_Node); end if; end if; Next (Param_Spec); end loop; end if; if Ekind (Id) = E_Function and then Ekind (Etype (Id)) = E_Anonymous_Access_Type and then Comes_From_Source (Id) then Error_Msg_N ("function in 'R'C'I unit cannot have access result", Error_Node); end if; end Validate_RCI_Subprogram_Declaration; ---------------------------------------------------- -- Validate_Remote_Access_Object_Type_Declaration -- ---------------------------------------------------- procedure Validate_Remote_Access_Object_Type_Declaration (T : Entity_Id) is Direct_Designated_Type : Entity_Id; Desig_Type : Entity_Id; begin -- We are called from Analyze_Full_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 and then not In_RT_Declaration) then return; end if; -- An access definition in the private part of a package is not a -- remote access type. Restrictions related to external streaming -- support for non-remote access types are enforced elsewhere. Note -- that In_Private_Part is never set on type entities: check flag -- on enclosing scope. if 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 or subtype. -- 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 not Is_Class_Wide_Type (Designated_Type (T)) then if In_RCI_Declaration 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 this check 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 several 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_ch4 Analyze_Explicit_Dereference -- 4. 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; -- 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); function Stream_Attributes_Available (Typ : Entity_Id) return Boolean; -- True if any stream attribute is available for Typ --------------------------------- -- Stream_Attributes_Available -- --------------------------------- function Stream_Attributes_Available (Typ : Entity_Id) return Boolean is begin return Stream_Attribute_Available (Typ, TSS_Stream_Read) or else Stream_Attribute_Available (Typ, TSS_Stream_Write) or else Stream_Attribute_Available (Typ, TSS_Stream_Input) or else Stream_Attribute_Available (Typ, TSS_Stream_Output); end Stream_Attributes_Available; -- Start of processing for Validate_RT_RAT_Component 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 (Base_Type (Typ)); if No (U_Typ) then U_Typ := Typ; end if; if Comes_From_Source (Typ) and then Is_Type (Typ) and then Ekind (Typ) /= E_Incomplete_Type then -- Check that the type can be meaningfully transmitted to another -- partition (E.2.2(8)). if (Ada_Version < Ada_2005 and then Has_Non_Remote_Access (U_Typ)) or else (Stream_Attributes_Available (Typ) and then No_External_Streaming (U_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_2005 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_Full_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; Val : Node_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_Aggregate | N_Component_Association | N_Index_Or_Discriminant_Constraint | N_Membership_Test | N_Op => return True; when N_Attribute_Reference => declare Attr : constant Name_Id := Attribute_Name (Parent (N)); begin return Attr /= Name_Address and then Attr /= Name_Access and then Attr /= Name_Unchecked_Access and then Attr /= Name_Unrestricted_Access; end; 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. Entities in a -- generic unit or within a preanalyzed expression are not checked: -- only their use in executable code matters. if Is_Primary (N) and then (not Inside_A_Generic or else Present (Enclosing_Generic_Body (N))) and then not In_Spec_Expression 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); -- Give an error for a reference to a nonstatic constant, unless the -- constant is in another GNAT library unit that is preelaborable. elsif Ekind (Entity (N)) = E_Constant and then not Is_Static_Expression (N) then E := Entity (N); Val := Constant_Value (E); if In_Internal_Unit (N) and then Enclosing_Comp_Unit_Node (N) /= Enclosing_Comp_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; -- If the value of the constant is a local variable that renames -- an aggregate, this is in itself legal. The aggregate may be -- expanded into a loop, but this does not affect preelaborability -- in itself. If some aggregate components are non-static, that is -- to say if they involve non static primaries, they will be -- flagged when analyzed. elsif Present (Val) and then Is_Entity_Name (Val) and then Is_Array_Type (Etype (Val)) and then not Comes_From_Source (Val) and then Nkind (Original_Node (Val)) = N_Aggregate then null; -- This is the error case else -- In GNAT mode or Relaxed RM Semantic mode, this is just a -- warning, to allow it to be judiciously turned off. -- Otherwise it is a real error. if GNAT_Mode or Relaxed_RM_Semantics 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;