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diff --git a/testsuite/tests/deriving/should_fail/T3621.hs b/testsuite/tests/deriving/should_fail/T3621.hs
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+{-# LANGUAGE GeneralizedNewtypeDeriving, MultiParamTypeClasses, FlexibleInstances, FunctionalDependencies, FlexibleContexts, UndecidableInstances, StandaloneDeriving #-}
+module T3621 where
+
+-- This one is ok, even though the deriving clause mentions 'a'
+-- which is not a parameter of 'T'
+class C a b 
+instance C a S
+data S = MkS
+
+newtype T = MkT S deriving( C a )
+
+
+-- But this one fails, and should fail
+class (Monad m) => MonadState s m | m -> s where
+
+newtype State s a = State { runState :: s -> (a, s) }
+instance Monad (State s) where {}
+instance MonadState s (State s) where {}
+
+newtype WrappedState s a = WS { runWS :: State s a }
+   deriving (Monad, MonadState state)
+--   deriving (Monad)
+
+deriving instance (MonadState state (State s))
+      => MonadState state (WrappedState s)
+
+-- ASSERT error
+-- deriving instance (MonadState state (State s), Monad (WrappedState s))
+--      => MonadState s (WrappedState s)
+
+
+-- We try
+--   instance MonadState state (State state a)
+--         => MonadState state (WrappedState state a)
+--
+-- Superclass needs (Monad (WrappedState state a))