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diff --git a/testsuite/tests/deriving/should_fail/T14339.hs b/testsuite/tests/deriving/should_fail/T14339.hs
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+{-# LANGUAGE DataKinds #-}
+{-# LANGUAGE GeneralizedNewtypeDeriving #-}
+{-# LANGUAGE UndecidableInstances #-}
+module Bug where
+
+import GHC.TypeLits
+
+newtype Foo = Foo Int
+
+class Bar a where
+  bar :: a
+
+instance (TypeError (Text "Boo")) => Bar Foo where
+  bar = undefined
+
+newtype Baz = Baz Foo
+  deriving Bar
+
+-- We derive:
+--
+--  instance TypeError (Text "Boo") => Bar Baz
+--
+-- And error out due to the TypeError. See also
+-- deriving/should_compile/T22696a, which uses StandaloneDeriving to write a
+-- valid instance with a TypeError constraint in its instance context.