[gnumeric] configure: mirror libgsf changes re Werror.

[Morten Welinder <mortenw src gnome org>]

commit 42257dde77ea1cd2f25225b460aaf09301dce231
Author: Morten Welinder <terra gnome org>
Date:   Thu Aug 1 18:47:28 2013 -0400

    configure: mirror libgsf changes re Werror.

 configure.ac |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 7662862..7866581 100644
--- a/configure.ac
+++ b/configure.ac
@@ -288,8 +288,10 @@ if test "$GCC" = yes -a "x$set_more_warnings" != xno; then
                SAVE_CFLAGS="$CFLAGS"
                CFLAGS="$CFLAGS $uwoption $option"
                AC_MSG_CHECKING([whether gcc understands $option])
+               dnl Include a system header so we ignore Werror=... flags
+               dnl that cause trouble.
                AC_COMPILE_IFELSE(
-                       [AC_LANG_PROGRAM([], [])],
+                       [AC_LANG_PROGRAM([[#include <stdio.h>]], [])],
                        [has_option=yes],
                        [has_option=no])
                CFLAGS="$SAVE_CFLAGS"