diff --git a/benchmark/Streamly/Benchmark/Data/Fold.hs b/benchmark/Streamly/Benchmark/Data/Fold.hs
index fcaa3d244d..cace1efbe6 100644
--- a/benchmark/Streamly/Benchmark/Data/Fold.hs
+++ b/benchmark/Streamly/Benchmark/Data/Fold.hs
@@ -220,7 +220,11 @@ demuxToIntMap :: Monad m =>
 demuxToIntMap f g = Stream.fold (FL.demuxToContainer f g)
 
 {-# INLINE demuxToHashMap  #-}
-demuxToHashMap :: (Monad m, Hashable k) =>
+demuxToHashMap :: (Monad m, Hashable k
+#if __GLASGOW_HASKELL__ == 810
+    , Eq k
+#endif
+    ) =>
     (a -> k) -> (a -> m (Fold m a b)) -> Stream m a -> m (HashMap k b)
 demuxToHashMap f g = Stream.fold (FL.demuxToContainer f g)
 
@@ -230,7 +234,11 @@ demuxToMapIO :: (MonadIO m, Ord k) =>
 demuxToMapIO f g = Stream.fold (FL.demuxToContainerIO f g)
 
 {-# INLINE demuxToHashMapIO  #-}
-demuxToHashMapIO :: (MonadIO m, Hashable k) =>
+demuxToHashMapIO :: (MonadIO m, Hashable k
+#if __GLASGOW_HASKELL__ == 810
+    , Eq k
+#endif
+    ) =>
     (a -> k) -> (a -> m (Fold m a b)) -> Stream m a -> m (HashMap k b)
 demuxToHashMapIO f g = Stream.fold (FL.demuxToContainerIO f g)