diff --git a/configure.ac b/configure.ac
index de1a94ff7..16376902b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -42,7 +42,7 @@ AC_PROG_LIBTOOL
 
 # If using GCC specifiy some additional parameters
 if test "x$GCC" = "xyes" ; then
-   CFLAGS="$CFLAGS -pipe -Wall"
+   CFLAGS="$CFLAGS -pipe -Wall -W"
 fi
 
 AC_CONFIG_FILES([Makefile src/Makefile])