--- a/libdecnumber/configure.ac	Thu Oct 25 07:37:49 2018 +0900
+++ b/libdecnumber/configure.ac	Thu Feb 13 11:34:05 2020 +0900
@@ -1,7 +1,7 @@
 # configure.ac for libdecnumber			-*- Autoconf -*-
 # Process this file with autoconf to generate a configuration script.
 
-# Copyright (C) 2005-2018 Free Software Foundation, Inc.
+# Copyright (C) 2005-2020 Free Software Foundation, Inc.
 
 # This file is part of GCC.
 
@@ -19,7 +19,6 @@
 # along with GCC; see the file COPYING3.  If not see
 # <http://www.gnu.org/licenses/>.
 
-AC_PREREQ(2.64)
 AC_INIT(libdecnumber, [ ], gcc-bugs@gcc.gnu.org, libdecnumber)
 AC_CONFIG_SRCDIR(decNumber.h)
 AC_CONFIG_MACRO_DIR(../config)