--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/genchecksum.c	Fri Jul 17 14:47:48 2009 +0900
@@ -0,0 +1,76 @@
+/* Generate checksums of executables for PCH validation
+   Copyright (C) 2005, 2007
+   Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT 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
+along with GCC; see the file COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
+
+#include "bconfig.h"
+#include "system.h"
+#include "md5.h"
+
+static void
+usage (void)
+{
+  fputs ("Usage: genchecksums <filename>\n", stderr);
+}
+
+static void
+dosum (const char *file)
+{
+  FILE *f;
+  unsigned char result[16];
+  int i;
+  
+  f = fopen (file, "rb");
+  if (!f)
+    {
+      fprintf (stderr, "opening %s: %s\n", file, xstrerror (errno));
+      exit (1);
+    }
+  
+  /* Some executable formats have timestamps in the first 16 bytes, yuck.  */
+  if (fseek (f, 16, SEEK_SET) != 0)
+     {
+      fprintf (stderr, "seeking in %s: %s\n", file, xstrerror (errno));
+      exit (1);
+    }
+  
+  if (md5_stream (f, result) != 0
+      || fclose (f) != 0)
+     {
+      fprintf (stderr, "reading %s: %s\n", file, xstrerror (errno));
+      exit (1);
+    }
+
+  fputs ("const unsigned char executable_checksum[16] = { ", stdout);
+  for (i = 0; i < 16; i++)
+    printf ("%#02x%s", result[i], i == 15 ? " };\n" : ", ");
+}
+
+int
+main (int argc, char ** argv)
+{
+  if (argc != 2)
+    {
+      usage ();
+      return 1;
+    }
+
+  dosum (argv[1]);
+
+  return 0;
+}