[GHC] #9456: Weird behavior with polymorphic function involving existential quantification and GADTs

[GHC]

#9456: Weird behavior with polymorphic function involving existential
quantification and GADTs
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        Reporter:  haasn             |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler (Type    |              Version:  7.8.2
  checker)                           |             Keywords:  GADTs,
      Resolution:                    |  TypeErrorMessages
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Incorrect         |  Unknown/Multiple
  warning at compile-time            |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by simonpj):

 * keywords:  GADTs => GADTs, TypeErrorMessages


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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9456#comment:11>
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