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

[GHC]

#8893: -XPolyKinds causes "*** Exception: Prelude.(!!): index too large"
-------------------------------------------------+-------------------------
        Reporter:  ghorn                         |            Owner:
            Type:  bug                           |           Status:  merge
        Priority:  normal                        |        Milestone:
       Component:  Compiler                      |          Version:
      Resolution:                                |  7.8.1-rc2
Operating System:  Unknown/Multiple              |         Keywords:
 Type of failure:  Compile-time crash            |  PolyKinds
       Test Case:                                |     Architecture:
  deriving/should_compile/T8893                  |  Unknown/Multiple
        Blocking:                                |       Difficulty:
                                                 |  Unknown
                                                 |       Blocked By:
                                                 |  Related Tickets:
-------------------------------------------------+-------------------------
Changes (by simonpj):

 * status:  new => merge
 * testcase:   => deriving/should_compile/T8893


Comment:

 Thanks for an excellent test case!

 Austin, please merge.

 Simon

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8893#comment:6>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler