--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/ada/libgnarl/a-sytaco.ads	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,94 @@
+------------------------------------------------------------------------------
+--                                                                          --
+--                         GNAT RUN-TIME COMPONENTS                         --
+--                                                                          --
+--         A D A . S Y N C H R O N O U S _ T A S K _ C O N T R O L          --
+--                                                                          --
+--                                 S p e c                                  --
+--                                                                          --
+--          Copyright (C) 1992-2017, Free Software Foundation, Inc.         --
+--                                                                          --
+-- This specification is derived from the Ada Reference Manual for use with --
+-- GNAT. The copyright notice above, and the license provisions that follow --
+-- apply solely to the  contents of the part following the private keyword. --
+--                                                                          --
+-- 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.                                     --
+--                                                                          --
+-- 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.      --
+--                                                                          --
+------------------------------------------------------------------------------
+
+with System.Task_Primitives;
+
+with Ada.Finalization;
+with Ada.Task_Identification;
+
+package Ada.Synchronous_Task_Control with
+  SPARK_Mode
+is
+   pragma Preelaborate;
+   --  In accordance with Ada 2005 AI-362
+
+   type Suspension_Object is limited private with
+     Default_Initial_Condition;
+
+   procedure Set_True (S : in out Suspension_Object) with
+     Global  => null,
+     Depends => (S    => null,
+                 null => S);
+
+   procedure Set_False (S : in out Suspension_Object) with
+     Global  => null,
+     Depends => (S    => null,
+                 null => S);
+
+   function Current_State (S : Suspension_Object) return Boolean with
+     Volatile_Function,
+     Global => Ada.Task_Identification.Tasking_State;
+
+   procedure Suspend_Until_True (S : in out Suspension_Object) with
+     Global  => null,
+     Depends => (S    => null,
+                 null => S);
+
+private
+   pragma SPARK_Mode (Off);
+
+   procedure Initialize (S : in out Suspension_Object);
+   --  Initialization for Suspension_Object
+
+   procedure Finalize (S : in out Suspension_Object);
+   --  Finalization for Suspension_Object
+
+   type Suspension_Object is
+     new Ada.Finalization.Limited_Controlled with
+   record
+      SO : System.Task_Primitives.Suspension_Object;
+      --  Use low-level suspension objects so that the synchronization
+      --  functionality provided by this object can be achieved using
+      --  efficient operating system primitives.
+   end record;
+
+   pragma Inline (Set_True);
+   pragma Inline (Set_False);
+   pragma Inline (Current_State);
+   pragma Inline (Suspend_Until_True);
+   pragma Inline (Initialize);
+   pragma Inline (Finalize);
+
+end Ada.Synchronous_Task_Control;