[GHC] #8720: ghc crash

[GHC]

#8720: ghc crash
------------------------------------------------+--------------------------
       Reporter:  guest                         |             Owner:
           Type:  bug                           |            Status:  new
       Priority:  normal                        |         Milestone:
      Component:  GHCi                          |           Version:  7.6.3
       Keywords:  ghci crash mvar thread block  |  Operating System:
   Architecture:  x86_64 (amd64)                |  Windows
     Difficulty:  Unknown                       |   Type of failure:  GHCi
     Blocked By:                                |  crash
Related Tickets:                                |         Test Case:
                                                |          Blocking:
------------------------------------------------+--------------------------
 ghc.exe: panic! (the 'impossible' happened)
   (GHC version 7.6.3 for i386-unknown-mingw32):
         thread blocked indefinitely in an MVar operation

 Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug

 I didn't try to reproduce it, but figured someone might want it.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8720>
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