[GHC] #11711: Typechecker assertion failure

[GHC]

#11711: Typechecker assertion failure
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        Reporter:  bgamari           |                Owner:
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:  8.0.1
       Component:  Compiler (Type    |              Version:  8.0.1-rc2
  checker)                           |
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  crash                              |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by goldfire):

 Nope. The culprit is that we're calling `isMetaTyVar` on a coercion
 variable from `simpl_top`. I've got a fix locally.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11711#comment:3>
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