diff --git a/src/runtime/haskell-bind/PGF2/FFI.hs b/src/runtime/haskell-bind/PGF2/FFI.hs
index 3f30631d8..9a65c186f 100644
--- a/src/runtime/haskell-bind/PGF2/FFI.hs
+++ b/src/runtime/haskell-bind/PGF2/FFI.hs
@@ -9,6 +9,7 @@ import Foreign.ForeignPtr
 import Control.Exception
 import GHC.Ptr
 import Data.Int(Int32)
+import Data.Word(Word)
 
 type Touch = IO ()