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diff --git a/testsuite/tests/typecheck/should_run/tcrun032.hs b/testsuite/tests/typecheck/should_run/tcrun032.hs
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+++ b/testsuite/tests/typecheck/should_run/tcrun032.hs
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+
+{-# LANGUAGE UndecidableInstances #-}
+
+-- This tests the recursive-dictionary stuff.
+
+module Main where
+
+data Fix f = In (f (Fix f)) 
+
+instance Show (f (Fix f)) => Show (Fix f) where
+  show (In x) = "In " ++ show x	-- No parens, but never mind
+
+instance Eq (f (Fix f)) => Eq (Fix f) where
+  (In x) == (In y) = x==y
+
+data L x = Nil | Cons Int x  deriving( Show, Eq )
+
+main = do { print (In Nil); 
+	    print (In Nil == In Nil) }
+