[GHC] #13970: Segmentation fault inside threadPaused

[GHC]

#13970: Segmentation fault inside threadPaused
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        Reporter:  albertov          |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Runtime System    |              Version:  8.2.1-rc3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by bgamari):

 I have managed to reproduce it a few times although it does seem to take a
 while. Moreover, it (perhaps not surprisingly) is quite dependent upon
 paralellism. I was unable to reproduce it in a reasonable amount of time
 on my dual-core, four-thread laptop. However, on my 4-core, eight-thread
 server I was able to reproduce it within ten minutes or so. How many cores
 does your test environment have?

 Also, for the sake of

 My first step is to test whether the fix to #13615 is to blame; the
 problem indeed appears to be a race condition and instrumenting the code
 can easily hide the problem. For instance, I was unable to reproduce the
 issue even once while running the program under `rr` overnight.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13970#comment:22>
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