#8563: Deriving with PolyKinds broken -------------------------------------+------------------------------------ Reporter: edsko | Owner: Type: bug | Status: new Priority: high | Milestone: Component: Compiler | Version: 7.7 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Unknown/Multiple Type of failure: None/Unknown | Difficulty: Unknown Test Case: | Blocked By: Blocking: | Related Tickets: -------------------------------------+------------------------------------ Comment (by nomeata): Thanks for the report, added as T8563 in a even simpler form: {{{ {-# LANGUAGE PolyKinds #-} module Tagged where newtype Tagged s b = Tagged b deriving Eq }}} The problems goes away without `PolyKinds` so it is related to that. Probably the `k` option to `Tagged` should not be explicitly given here. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/8563#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler