--
atomicModifyIORef :: IORef a -> (a -> (a,b)) -> IO b
#if defined(__GLASGOW_HASKELL__)
atomicModifyIORef (IORef (STRef r#)) f = IO $ \s -> atomicModifyMutVar# r# f s
--
atomicModifyIORef :: IORef a -> (a -> (a,b)) -> IO b
#if defined(__GLASGOW_HASKELL__)
atomicModifyIORef (IORef (STRef r#)) f = IO $ \s -> atomicModifyMutVar# r# f s