[GHC] #13707: xmobar crashes with segmentation faults?

[GHC]

#13707: xmobar crashes with segmentation faults?
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        Reporter:  bgamari           |                Owner:  (none)
            Type:  bug               |               Status:  infoneeded
        Priority:  highest           |            Milestone:  8.2.1
       Component:  Compiler          |              Version:  8.2.1-rc2
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  crash or panic                     |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by rezb1t):

 Hi there! I noticed you needed a coredump some time ago, and was only now
 able to get one, as it was difficult to reproduce this bug using my setup.
 It has only happened to me a handful of times so far, probably 3-4 since
 GHC 8.2.1 came out.

 I am using NixOS latest unstable, GHC 8.2.1, and xmonad with xmobar.

 This coredump was truncated down to 500kb but if you need a larger one,
 let me know and I will do my best to get you one.

 Thanks!

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13707#comment:13>
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