diff --git a/Data/Attoparsec/ByteString/Internal.hs b/Data/Attoparsec/ByteString/Internal.hs
--- a/Data/Attoparsec/ByteString/Internal.hs
+++ b/Data/Attoparsec/ByteString/Internal.hs
@@ -369,7 +369,7 @@
      | more == Complete ->
        succ t pos more Nothing
      | otherwise ->
-       let succ' t' pos' more' = let !w = Buf.unsafeIndex t pos_
+       let succ' t' pos' more' = let !w = Buf.unsafeIndex t' pos_
                                  in succ t' pos' more' (Just w)
            lose' t' pos' more' = succ t' pos' more' Nothing
        in prompt t pos more lose' succ'
diff --git a/attoparsec.cabal b/attoparsec.cabal
--- a/attoparsec.cabal
+++ b/attoparsec.cabal
@@ -1,5 +1,5 @@
 name:            attoparsec
-version:         0.12.1.0
+version:         0.12.1.1
 license:         BSD3
 license-file:    LICENSE
 category:        Text, Parsing