raise an error if stack fails in lxc
diff --git a/tools/build_lxc.sh b/tools/build_lxc.sh
index 9cbbedf..b629183 100755
--- a/tools/build_lxc.sh
+++ b/tools/build_lxc.sh
@@ -301,6 +301,11 @@
     done
 
     kill $TAIL_PID
+
+    if grep -q "stack.sh failed" $ROOTFS/$DEST/run.sh.log; then
+        exit 1
+    fi
+
     echo ""
     echo "Finished - Zip-a-dee Doo-dah!"
 fi