[GHC] #14299: GHCi for GHC 8.2.1 crashed with simple function?

[GHC]

#14299: GHCi for GHC 8.2.1 crashed with simple function?
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        Reporter:  mathiassm   |                Owner:  (none)
            Type:  bug         |               Status:  new
        Priority:  normal      |            Milestone:
       Component:  GHCi        |              Version:  8.2.1
      Resolution:              |             Keywords:
Operating System:  MacOS X     |         Architecture:  x86_64 (amd64)
 Type of failure:  GHCi crash  |            Test Case:
      Blocked By:              |             Blocking:
 Related Tickets:              |  Differential Rev(s):
       Wiki Page:              |
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Comment (by bgamari):

 Well, it definitely seems like there is a bug here regardless of whether
 or not I can reproduce it. `MVar`s are mutable variables generally used in
 concurrent settings, so there is definitely the potential for bugs here.

 > Thank you for your time (and sorry!)

 No need to be sorry! Thanks for reporting the bug.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14299#comment:5>
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