# ===========================================================================#    https://www.gnu.org/software/autoconf-archive/ax_recursive_eval.html# ===========================================================================## SYNOPSIS##   AX_RECURSIVE_EVAL(VALUE, RESULT)## DESCRIPTION##   Interpolate the VALUE in loop until it doesn't change, and set the#   result to $RESULT. WARNING: It's easy to get an infinite loop with some#   unsane input.## LICENSE##   Copyright (c) 2008 Alexandre Duret-Lutz <adl@gnu.org>##   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, see <https://www.gnu.org/licenses/>.##   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 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. #serial 1 AC_DEFUN([AX_RECURSIVE_EVAL],[_lcl_receval="$1"$2=`(test "x$prefix" = xNONE && prefix="$ac_default_prefix"     test "x$exec_prefix" = xNONE && exec_prefix="${prefix}"     _lcl_receval_old=''     while test "[$]_lcl_receval_old" != "[$]_lcl_receval"; do       _lcl_receval_old="[$]_lcl_receval"       eval _lcl_receval="\"[$]_lcl_receval\""     done     echo "[$]_lcl_receval")`])