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diff --git a/testsuite/tests/deriving/should_compile/drv001.hs b/testsuite/tests/deriving/should_compile/drv001.hs
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index 0000000000..694af6a50f
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+++ b/testsuite/tests/deriving/should_compile/drv001.hs
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+-- !!! canonical weird example for "deriving"
+module ShouldSucceed where
+
+data X a b
+  = C1 (T a)
+  | C2 (Y b)
+  | C3 (X b a)
+  deriving (Read, Show)
+
+data Y b
+  = D1
+  | D2 (X Int b)
+  deriving (Read, Show)
+
+data T a
+  = E1
+
+instance Eq a => Show (T a) where
+    showsPrec = error "show"
+instance Eq a => Read (T a) where
+    readsPrec = error "read"