diff --git a/XMonad/Layout/Spacing.hs b/XMonad/Layout/Spacing.hs
index c54ef502..359487a4 100644
--- a/XMonad/Layout/Spacing.hs
+++ b/XMonad/Layout/Spacing.hs
@@ -1,4 +1,5 @@
 {-# LANGUAGE FlexibleInstances, MultiParamTypeClasses, DeriveDataTypeable #-}
+{-# LANGUAGE PatternGuards #-}
 
 -----------------------------------------------------------------------------
 -- |