[GHC] #10031: coerce can cause compiler to loop

[GHC]

#10031: coerce can cause compiler to loop
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        Reporter:  glguy             |                   Owner:  goldfire
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:
       Component:  Compiler          |                 Version:  7.10.1-rc1
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:  x86_64
 Type of failure:  Compile-time      |  (amd64)
  crash                              |               Test Case:
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:
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Comment (by goldfire):

 Thanks to glguy for such a nice, tiny test case and to Joachim (nomeata)
 for the dump. I'm able to solve this without testing! Just add a critical
 missing `not` in the bowels of `kick_out`. Will validate and push shortly.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10031#comment:4>
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