--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/ada/libgnat/s-flocon.ads	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,59 @@
+------------------------------------------------------------------------------
+--                                                                          --
+--                         GNAT RUN-TIME COMPONENTS                         --
+--                                                                          --
+--                 S Y S T E M . F L O A T _ C O N T R O L                  --
+--                                                                          --
+--                                 S p e c                                  --
+--                                                                          --
+--                     Copyright (C) 2000-2017, AdaCore                     --
+--                                                                          --
+-- 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.      --
+--                                                                          --
+------------------------------------------------------------------------------
+
+--  Control functions for floating-point unit
+
+package System.Float_Control is
+   pragma Pure;
+   --  This is not fully correct, but this unit is with-ed by pure units
+   --  (eg s-imgrea).
+
+   procedure Reset;
+   pragma Inline (Reset);
+   --  Reset the floating-point processor to the default state needed to get
+   --  correct Ada semantics for the target. Some third party tools change
+   --  the settings for the floating-point processor. Reset can be called
+   --  to reset the floating-point processor into the mode required by GNAT
+   --  for correct operation. Use this call after a call to foreign code if
+   --  you suspect incorrect floating-point operation after the call.
+   --
+   --  For example under Windows NT some system DLL calls change the default
+   --  FPU arithmetic to 64 bit precision mode. However, since in Ada 95 it
+   --  is required to provide full access to the floating-point types of the
+   --  architecture, GNAT requires full 80-bit precision mode, and Reset makes
+   --  sure this mode is established.
+   --
+   --  Similarly on the PPC processor, it is important that overflow and
+   --  underflow exceptions be disabled.
+   --
+   --  The call to Reset simply has no effect if the target environment
+   --  does not give rise to such concerns.
+end System.Float_Control;