[GHC] #8893: -XPolyKinds causes "*** Exception: Prelude.(!!): index too large"

[GHC]

#8893: -XPolyKinds causes "*** Exception: Prelude.(!!): index too large"
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        Reporter:  ghorn               |            Owner:
            Type:  bug                 |           Status:  new
        Priority:  normal              |        Milestone:
       Component:  Compiler            |          Version:  7.8.1-rc2
      Resolution:                      |         Keywords:  PolyKinds
Operating System:  Unknown/Multiple    |     Architecture:
 Type of failure:  Compile-time crash  |  Unknown/Multiple
       Test Case:                      |       Difficulty:  Unknown
        Blocking:                      |       Blocked By:
                                       |  Related Tickets:
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Comment (by Simon Peyton Jones <simonpj@…>):

 In [changeset:"ffed708c30f2d1d4b4c5cd08d9c19aeb0bb623ec/ghc"]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="ffed708c30f2d1d4b4c5cd08d9c19aeb0bb623ec"
 Apply the kind subst to the (kinds of the) quanitifed tyvars in
 deriveTyData

 I've elaboated Note [Unify kinds in deriving] to explain
 what is going on here.

 The change fixes Trac #8893.
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8893#comment:4>
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