Index: configure.in.in
===================================================================
--- configure.in.in	(revision 18976)
+++ configure.in.in	(working copy)
@@ -295,6 +295,8 @@
 have_gnuc_visibility=no
 if test x"$enable_visibility" != x"no"; then
   dnl Check whether the compiler supports the visibility attribute
+  save_CFLAGS="$CFLAGS"
+  CFLAGS="$CFLAGS -Wall -Werror"
   AC_MSG_CHECKING([whether $CC supports the GNUC visibility attribute])
   AC_COMPILE_IFELSE(AC_LANG_SOURCE(
   [
@@ -309,6 +311,7 @@
   [
     AC_MSG_RESULT([no])
   ])
+  CFLAGS="$save_CFLAGS"
 fi
 if test x"$have_gnuc_visibility" = x"yes"; then
   PLATFORM_CPPFLAGS="$PLATFORM_CPPFLAGS -DHAVE_GNUC_VISIBILITY"