1 files changed, 4 insertions, 2 deletions

diff --git a/src/Data/Torrent.hs b/src/Data/Torrent.hs
index 94506d1c..d6f141a8 100644
--- a/src/Data/Torrent.hs
+++ b/src/Data/Torrent.hs
@@ -612,7 +612,8 @@ data Piece a = Piece
   , pieceData  :: !a
   } deriving (Show, Read, Eq, Functor, Typeable)
 
-instance NFData (Piece a)
+instance NFData a => NFData (Piece a) where
+  rnf (Piece a b) = rnf a `seq` rnf b
 
 -- | Payload bytes are omitted.
 instance Pretty (Piece a) where
@@ -653,7 +654,8 @@ makeLensesFor [("piPieceLength", "pieceLength")] ''PieceInfo
 -- | Concatenation of all 20-byte SHA1 hash values.
 makeLensesFor [("piPieceHashes", "pieceHashes")] ''PieceInfo
 
-instance NFData PieceInfo
+instance NFData PieceInfo where
+  rnf (PieceInfo a (HashList b)) = rnf a `seq` rnf b
 
 instance Default PieceInfo where
   def = PieceInfo 1 def