dnl AC_GNU_SOURCE version: 1 updated: 2022/11/13 14:26:50
dnl -------------
AC_DEFUN([AC_GNU_SOURCE], [
	CF_XOPEN_SOURCE
	dnl AC_MSG_WARN([use CF_XOPEN_SOURCE])
	dnl CPPFLAGS="$CPPFLAGS -D_DEFAULT_SOURCE"
] )
