+dnl Common configure.ac fragment
+dnl
+dnl Copyright (C) 2012-2020 Free Software Foundation, Inc.
+dnl
+dnl This file is free software; you can redistribute it and/or modify
+dnl it under the terms of the GNU General Public License as published by
+dnl the Free Software Foundation; either version 3 of the License, or
+dnl (at your option) any later version.
+dnl
+dnl This program is distributed in the hope that it will be useful,
+dnl but WITHOUT ANY WARRANTY; without even the implied warranty of
+dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+dnl GNU General Public License for more details.
+dnl
+dnl You should have received a copy of the GNU General Public License
+dnl along with this program; see the file COPYING3. If not see
+dnl <http://www.gnu.org/licenses/>.
+dnl
+
+# AC_EGREP_CPP_FOR_BUILD(PATTERN, PROGRAM,
+# [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND])
+# ------------------------------------------------------
+AC_DEFUN([AC_EGREP_CPP_FOR_BUILD],
+[AC_LANG_PREPROC_REQUIRE()dnl
+AC_REQUIRE([AC_PROG_EGREP])dnl
+AC_LANG_CONFTEST([AC_LANG_SOURCE([[$2]])])
+AS_IF([dnl eval is necessary to expand ac_cpp.
+dnl Ultrix and Pyramid sh refuse to redirect output of eval, so use subshell.
+(eval "$ac_cpp_for_build conftest.$ac_ext") 2>&AS_MESSAGE_LOG_FD |
+dnl Quote $1 to prevent m4 from eating character classes
+ $EGREP "[$1]" >/dev/null 2>&1],
+ [$3],
+ [$4])
+rm -f conftest*
+])# AC_EGREP_CPP_FOR_BUILD
+