--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/ada/libgnat/a-secain.adb	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,59 @@
+------------------------------------------------------------------------------
+--                                                                          --
+--                         GNAT LIBRARY COMPONENTS                          --
+--                                                                          --
+--   A D A . S T R I N G S . E Q U A L _ C A S E _ I N S E N S I T I V E    --
+--                                                                          --
+--                                 B o d y                                  --
+--                                                                          --
+--          Copyright (C) 2004-2017, 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.                                     --
+--                                                                          --
+-- 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/>.                                          --
+--                                                                          --
+-- This unit was originally developed by Matthew J Heaney.                  --
+------------------------------------------------------------------------------
+
+with Ada.Characters.Handling;  use Ada.Characters.Handling;
+
+function Ada.Strings.Equal_Case_Insensitive
+  (Left, Right : String) return Boolean
+is
+   LI : Integer := Left'First;
+   RI : Integer := Right'First;
+
+begin
+   if Left'Length /= Right'Length then
+      return False;
+   end if;
+
+   if Left'Length = 0 then
+      return True;
+   end if;
+
+   loop
+      if To_Lower (Left (LI)) /= To_Lower (Right (RI)) then
+         return False;
+      end if;
+
+      if LI = Left'Last then
+         return True;
+      end if;
+
+      LI := LI + 1;
+      RI := RI + 1;
+   end loop;
+end Ada.Strings.Equal_Case_Insensitive;