[GHC] #15449: Nondeterministic Failure on aarch64 with -jn, n > 1

[GHC]

#15449: Nondeterministic Failure on aarch64 with -jn, n > 1
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        Reporter:  tmobile           |                Owner:  tmobile
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.8.1
       Component:  Compiler          |              Version:  8.4.3
      Resolution:                    |             Keywords:
Operating System:  Linux             |         Architecture:  aarch64
 Type of failure:  Compile-time      |            Test Case:
  crash or panic                     |
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by tmobile):

 For what it's worth,  the two attached programs work just fine with -N on
 my TX2, compiled with unmodified GHC 8.4.3. They're both classic "start n
 threads that increment a shared variable m times" tests, one with MVar and
 one with IORef.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15449#comment:17>
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