[GHC] #8714: ExistentialQuantification plus DeriveDataTypeable leads to core lint error

[GHC]

#8714: ExistentialQuantification plus DeriveDataTypeable leads to core lint error
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        Reporter:  CoreyOConnor      |            Owner:
            Type:  bug               |           Status:  new
        Priority:  normal            |        Milestone:  7.8.1
       Component:  Compiler          |          Version:  7.8.1-rc1
      Resolution:                    |         Keywords:
Operating System:  Unknown/Multiple  |     Architecture:  x86_64 (amd64)
 Type of failure:  None/Unknown      |       Difficulty:  Unknown
       Test Case:                    |       Blocked By:
        Blocking:                    |  Related Tickets:
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Changes (by thoughtpolice):

 * version:  7.6.3 => 7.8.1-rc1
 * milestone:   => 7.8.1


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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8714#comment:7>
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