dnl
dnl   Copyright (C) 2011-2014 Peter Breitenlohner <tex-live@tug.org>
dnl
dnl   This file is free software; the copyright holder
dnl   gives unlimited permission to copy and/or distribute it,
dnl   with or without modifications, as long as this notice is preserved.
dnl
dnl --------------------------------------------------------
dnl
dnl  m4-include this file to define the current libpng version
m4_define([libpng_version], [1.6.8])