diff --git a/package/archlinux/PKGBUILD-gcc47 b/package/archlinux/PKGBUILD-gcc47
index 2101e11db..acda7ac47 100644
--- a/package/archlinux/PKGBUILD-gcc47
+++ b/package/archlinux/PKGBUILD-gcc47
@@ -14,6 +14,10 @@ provides=('magnum-git')
 _rootdir=$startdir/../../
 
 build() {
+    # Disable flags unknown to GCC 4.7
+    newcxxflags=$(echo $CXXFLAGS | sed s/-fstack-protector-strong.//g)
+    export CXXFLAGS="$newcxxflags"
+
     if [ ! -d "$_rootdir/build-gcc47" ] ; then
         mkdir "$_rootdir/build-gcc47"
         cd "$_rootdir/build-gcc47"