--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/config/gthr.m4	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,27 @@
+dnl Copyright (C) 2012 Free Software Foundation, Inc.
+dnl This file is free software, distributed under the terms of the GNU
+dnl General Public License.  As a special exception to the GNU General
+dnl Public License, this file may be distributed as part of a program
+dnl that contains a configuration script generated by Autoconf, under
+dnl the same distribution terms as the rest of that program.
+
+dnl Define header location by thread model
+
+dnl usage: GCC_AC_THREAD_HEADER([thread_model])
+AC_DEFUN([GCC_AC_THREAD_HEADER],
+[
+case $1 in
+    aix)	thread_header=config/rs6000/gthr-aix.h ;;
+    dce)	thread_header=config/pa/gthr-dce.h ;;
+    lynx)	thread_header=config/gthr-lynx.h ;;
+    mipssde)	thread_header=config/mips/gthr-mipssde.h ;;
+    posix)	thread_header=gthr-posix.h ;;
+    rtems)	thread_header=config/gthr-rtems.h ;;
+    single)	thread_header=gthr-single.h ;;
+    tpf)	thread_header=config/s390/gthr-tpf.h ;;
+    vxworks)	thread_header=config/gthr-vxworks.h ;;
+    win32)	thread_header=config/i386/gthr-win32.h ;;
+esac
+AC_SUBST(thread_header)
+])
+