+dnl Check whether a warning flag is accepted.
+dnl If so, add it to CFLAGS.
+dnl Example: PSPP_ENABLE_WARNING(-Wdeclaration-after-statement)
+AC_DEFUN([PSPP_ENABLE_WARNING],
+[
+ m4_define([pspp_cv_name], [pspp_cv_[]m4_translit([$1], [-], [_])])dnl
+ AC_CACHE_CHECK([whether $CC accepts $1], [pspp_cv_name],
+ [pspp_save_CFLAGS="$CFLAGS"
+ CFLAGS="$CFLAGS $1"
+ AC_COMPILE_IFELSE([AC_LANG_PROGRAM(,)], [pspp_cv_name[]=yes], [pspp_cv_name[]=no])
+ CFLAGS="$pspp_save_CFLAGS"])
+ if test $pspp_cv_name = yes; then
+ CFLAGS="$CFLAGS $1"
+ fi
+])
+