--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/ada/scn.ads	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,83 @@
+------------------------------------------------------------------------------
+--                                                                          --
+--                         GNAT COMPILER COMPONENTS                         --
+--                                                                          --
+--                                  S C N                                   --
+--                                                                          --
+--                                 S p e c                                  --
+--                                                                          --
+--          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.      --
+--                                                                          --
+------------------------------------------------------------------------------
+
+--  This package contains the lexical analyzer routines. This is used by the
+--  compiler for scanning Ada source files.
+
+with Casing; use Casing;
+with Errout; use Errout;
+with Scng;
+with Style;  --  use Style;
+with Types;  use Types;
+
+package Scn is
+
+   procedure Initialize_Scanner
+     (Unit  : Unit_Number_Type;
+      Index : Source_File_Index);
+   --  Initialize lexical scanner for scanning a new file. The caller has
+   --  completed the construction of the Units.Table entry for the specified
+   --  Unit and Index references the corresponding source file. A special case
+   --  is when Unit = No_Unit, and Index corresponds to the source index for
+   --  reading the configuration pragma file.
+
+   function Determine_Token_Casing return Casing_Type;
+   --  Determines the casing style of the current token, which is either a
+   --  keyword or an identifier. See also package Casing.
+
+   procedure Post_Scan;
+   --  Create nodes for tokens: Char_Literal, Identifier, Real_Literal,
+   --  Integer_Literal, String_Literal and Operator_Symbol.
+
+   procedure Scan_Reserved_Identifier (Force_Msg : Boolean);
+   --  This procedure is called to convert the current token, which the caller
+   --  has checked is for a reserved word, to an equivalent identifier. This is
+   --  of course only used in error situations where the parser can detect that
+   --  a reserved word is being used as an identifier. An appropriate error
+   --  message, pointing to the token, is also issued if either this is the
+   --  first occurrence of misuse of this identifier, or if Force_Msg is True.
+
+   -------------
+   -- Scanner --
+   -------------
+
+   --  The scanner used by the compiler is an instantiation of the
+   --  generic package Scng with routines appropriate to the compiler
+
+   package Scanner is new Scng
+     (Post_Scan    => Post_Scan,
+      Error_Msg    => Error_Msg,
+      Error_Msg_S  => Error_Msg_S,
+      Error_Msg_SC => Error_Msg_SC,
+      Error_Msg_SP => Error_Msg_SP,
+      Style        => Style.Style_Inst);
+
+   procedure Scan renames Scanner.Scan;
+   --  Scan scans out the next token, and advances the scan state accordingly
+   --  (see package Scans for details). If the scan encounters an illegal
+   --  token, then an error message is issued pointing to the bad character,
+   --  and Scan returns a reasonable substitute token of some kind.
+
+end Scn;