-- --
-- S p e c --
-- --
--- --
--- Copyright (C) 1992-2000 Free Software Foundation, Inc. --
+-- Copyright (C) 1992-2009, 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 2, or (at your option) any later ver- --
+-- 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 COPYING. If not, write --
--- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
--- MA 02111-1307, USA. --
--- --
--- As a special exception, if other files instantiate generics from this --
--- unit, or you link this unit with other files to produce an executable, --
--- this unit does not by itself cause the resulting executable to be --
--- covered by the GNU General Public License. This exception does not --
--- however invalidate any other reasons why the executable file might be --
--- covered by the GNU Public License. --
+-- or FITNESS FOR A PARTICULAR PURPOSE. --
+-- --
+-- As a special exception under Section 7 of GPL version 3, you are granted --
+-- additional permissions described in the GCC Runtime Library Exception, --
+-- version 3.1, as published by the Free Software Foundation. --
+-- --
+-- You should have received a copy of the GNU General Public License and --
+-- a copy of the GCC Runtime Library Exception along with this program; --
+-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
+-- <http://www.gnu.org/licenses/>. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
+
+-- This unit provides the basic support for controlled (finalizable) types
+
with Ada.Streams;
+with Ada.Unchecked_Conversion;
+
package System.Finalization_Root is
-pragma Preelaborate (Finalization_Root);
+ pragma Preelaborate;
- type Root_Controlled;
+ type Root_Controlled is tagged;
type Finalizable_Ptr is access all Root_Controlled'Class;
+ function To_Finalizable_Ptr is
+ new Ada.Unchecked_Conversion (Address, Finalizable_Ptr);
+
+ function To_Addr is
+ new Ada.Unchecked_Conversion (Finalizable_Ptr, Address);
+
type Empty_Root_Controlled is abstract tagged null record;
-- Just for the sake of Controlled equality (see Ada.Finalization)
procedure Finalize (Object : in out Root_Controlled);
procedure Adjust (Object : in out Root_Controlled);
- procedure Write (Stream : access Ada.Streams.Root_Stream_Type'Class;
- Item : in Root_Controlled);
- procedure Read (Stream : access Ada.Streams.Root_Stream_Type'Class;
- Item : out Root_Controlled);
+ -- Stream-oriented attributes for Root_Controlled. These must be empty so
+ -- as to not copy the finalization chain pointers. They are declared in
+ -- a nested package so that they do not create primitive operations of
+ -- Root_Controlled. Otherwise this would add unwanted primitives to (the
+ -- full view of) Ada.Finalization.Limited_Controlled, which would cause
+ -- trouble in cases where a limited controlled type is used as the
+ -- designated type of a remote access-to-classwide type.
+
+ package Stream_Attributes is
+
+ procedure Write
+ (Stream : not null access Ada.Streams.Root_Stream_Type'Class;
+ Item : Root_Controlled) is null;
+
+ procedure Read
+ (Stream : not null access Ada.Streams.Root_Stream_Type'Class;
+ Item : out Root_Controlled) is null;
+
+ end Stream_Attributes;
+
+ for Root_Controlled'Read use Stream_Attributes.Read;
+ for Root_Controlled'Write use Stream_Attributes.Write;
- for Root_Controlled'Read use Read;
- for Root_Controlled'Write use Write;
end System.Finalization_Root;
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