diff --git a/tests/T229.hs b/tests/T229.hs
index 1d8c157b29a7a3c70493dbc46d50f5d826af8025..9f4fd88594d6472bf568711e5ce99ce2657c6907 100644
--- a/tests/T229.hs
+++ b/tests/T229.hs
@@ -1,3 +1,5 @@
+{-# LANGUAGE CPP #-}
+
 import Data.Array.MArray
 import Data.Array.IO
 import Data.Word