[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:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.6.1
       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 bgamari):

 Actually, I don't think it's true that what suggestion in comment:2 is
 quite right. The fact that there is a barrier is embodied by the `True`
 argument of `genLoadW` (which the definition site binds to the name
 `atomic`). This gets lowered as a `seq_cst` load.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15449#comment:5>
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