##### http://autoconf-archive.cryp.to/ax_configure_args.html
#
# SYNOPSIS
#
#   AX_CONFIGURE_ARGS
#
# DESCRIPTION
#
#   Helper macro for AX_ENABLE_BUILDDIR and AX_ENABLE_BUILDDIR_UNAME
#
#   The traditional way of starting a subdir-configure is running the
#   script with ${1+"$@"} but since autoconf 2.60 this is broken.
#   Instead we have to rely on eval'ing $ac_configure_args however some
#   old autoconf versions do not provide that. To ensure maximum
#   portability of autoconf extension macros this helper can be
#   AC_REQUIRE'd so that $ac_configure_args will alsways be present.
#
#   Sadly, the traditional "exec $SHELL" of the enable_builddir macros
#   is spoiled now and must be replaced by "eval + exit $?".
#
#   Example:
#
#      AC_DEFUN([AX_ENABLE_SUBDIR],[dnl
#        AC_REQUIRE([AX_CONFIGURE_ARGS])dnl
#        eval $SHELL $ac_configure_args || exit $?
#        ...])
#
# LAST MODIFICATION
#
#   2007-02-01
#
# COPYLEFT
#
#   Copyright (c) 2007 Guido U. Draheim <guidod@gmx.de>
#
#   This program 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 2 of the
#   License, or (at your option) any later version.
#
#   This program 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 this program; if not, write to the Free Software
#   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
#   02111-1307, USA.
#
#   As a special exception, the respective Autoconf Macro's copyright
#   owner gives unlimited permission to copy, distribute and modify the
#   configure scripts that are the output of Autoconf when processing
#   the Macro. You need not follow the terms of the GNU General Public
#   License when using or distributing such scripts, even though
#   portions of the text of the Macro appear in them. The GNU General
#   Public License (GPL) does govern all other use of the material that
#   constitutes the Autoconf Macro.
#
#   This special exception to the GPL applies to versions of the
#   Autoconf Macro released by the Autoconf Macro Archive. When you
#   make and distribute a modified version of the Autoconf Macro, you
#   may extend this special exception to the GPL to apply to your
#   modified version as well.

AC_DEFUN([AX_CONFIGURE_ARGS],[
   # [$]@ is unsable in 2.60+ but earlier autoconf had no ac_configure_args
   if test "${ac_configure_args+set}" != "set" ; then
      ac_configure_args=
      for ac_arg in ${1+"[$]@"}; do
         ac_configure_args="$ac_configure_args '$ac_arg'"
      done
   fi
])