[GHC] #8985: Strange kind error with type family, GADTs, data kinds, and kind polymorphism

[GHC]

#8985: Strange kind error with type family, GADTs, data kinds, and kind
polymorphism
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        Reporter:  kosmikus                   |            Owner:
            Type:  bug                        |           Status:  new
        Priority:  normal                     |        Milestone:
       Component:  Compiler (Type checker)    |          Version:  7.8.1
      Resolution:                             |         Keywords:
Operating System:  Unknown/Multiple           |     Architecture:
 Type of failure:  GHC rejects valid program  |  Unknown/Multiple
       Test Case:                             |       Difficulty:  Unknown
        Blocking:                             |       Blocked By:
                                              |  Related Tickets:
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Comment (by simonpj):

 Thank you. It's a palpable bug in the kind unifier.  Working on it.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8985#comment:1>
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