[GHC] #9309: Regression when building the 'sizes' application

[GHC]

#9309: Regression when building the 'sizes' application
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       Reporter:            |             Owner:
  JohnWiegley               |            Status:  new
           Type:  bug       |         Milestone:  7.10.1
       Priority:  normal    |           Version:  7.8.3
      Component:  Compiler  |  Operating System:  Unknown/Multiple
       Keywords:            |   Type of failure:  GHC rejects valid program
   Architecture:            |         Test Case:
  Unknown/Multiple          |          Blocking:
     Difficulty:  Unknown   |
     Blocked By:            |
Related Tickets:            |
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 I have a package on Hackage called `sizes`.  It builds fine with GHC
 7.8.2, but when building with 7.8.3 I get:

     ghc: panic! (the 'impossible' happened)
       (GHC version 7.8.3 for x86_64-apple-darwin):
         make_exp (App _ (Coercion _))

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9309>
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