diff --git a/Basement/Terminal/Size.hsc b/Basement/Terminal/Size.hsc
--- a/Basement/Terminal/Size.hsc
+++ b/Basement/Terminal/Size.hsc
@@ -123,4 +123,4 @@
 invalidHandleValue :: IntPtr
-invalidHandleValue = #{const INVALID_HANDLE_VALUE}
+invalidHandleValue = Prelude.fromIntegral (#{const (INT_PTR)INVALID_HANDLE_VALUE} :: Int)

 stdOutputHandle :: CULong