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diff --git a/testsuite/tests/safeHaskell/safeLanguage/SafeLang06.hs b/testsuite/tests/safeHaskell/safeLanguage/SafeLang06.hs
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+{-# LANGUAGE GeneralizedNewtypeDeriving #-}
+
+-- Here we allow it to succeed (No SAFE)
+
+-- | We use newtype to create an isomorphic type to Int
+-- with a reversed Ord dictionary. We now use the MinList
+-- API of Y1 to create a new MinList. Then we use newtype
+-- deriving to convert the newtype MinList to an Int
+-- MinList. This final result breaks the invariants of
+-- MinList which shouldn't be possible with the exposed
+-- API of Y1.
+module Main where
+
+import SafeLang06_A
+
+class IntIso t where
+    intIso :: c t -> c Int
+
+instance IntIso Int where
+    intIso = id
+
+newtype Down a = Down a deriving (Eq, Show, IntIso)
+
+instance Ord a => Ord (Down a) where
+    compare (Down a) (Down b) = compare b a
+
+forceInt :: MinList Int -> MinList Int
+forceInt = id
+
+a1, a2 :: MinList Int
+a1 = foldl insertMinList (newMinList $ head nums) (tail nums)
+a2 = forceInt $ intIso $ foldl (\x y -> insertMinList x $ Down y) (newMinList $ Down $ head nums) (tail nums)
+
+nums :: [Int]
+nums = [1,4,0,1,-5,2,3,5,-1,2,0,0,-4,-3,9]
+
+main = do
+    printIntMinList a1
+    printIntMinList a2
+