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diff --git a/testsuite/tests/mdo/should_compile/mdo002.hs b/testsuite/tests/mdo/should_compile/mdo002.hs
new file mode 100644
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+++ b/testsuite/tests/mdo/should_compile/mdo002.hs
@@ -0,0 +1,23 @@
+{-# OPTIONS -XRecursiveDo #-}
+
+-- test of user defined instance of MonadFix
+
+module Main (main) where
+
+import Control.Monad.Fix
+
+data X a = X a deriving Show
+
+instance Monad X where
+  return      = X
+  (X a) >>= f = f a
+
+instance MonadFix X where
+  mfix f = fix (f . unX) 
+         where unX ~(X x) = x
+
+z :: X [Int]
+z = mdo x <- return (1:x)
+	return (take 4 x)
+
+main = print z