--- tar-0.3.1.0-orig/Codec/Archive/Tar/Write.hs	2009-06-06 23:51:00.000000000 +1000
+++ tar-0.3.1.0/Codec/Archive/Tar/Write.hs	2011-12-24 09:36:10.928384175 +1100
@@ -119,7 +119,7 @@
 putString n s = take n s ++ fill (n - length s) '\NUL'
 
 --TODO: check integer widths, eg for large file sizes
-putOct :: Integral a => FieldWidth -> a -> String
+putOct :: (Integral a, Show a) => FieldWidth -> a -> String
 putOct n x =
   let octStr = take (n-1) $ showOct x ""
    in fill (n - length octStr - 1) '0'