[GHC] #3875: DPH QuickHull example crashes on SPARC with -N > 1

[GHC]

#3875: DPH QuickHull example crashes on SPARC with -N > 1
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    Reporter:  benl            |        Owner:  benl         
        Type:  bug             |       Status:  assigned     
    Priority:  high            |    Milestone:  6.12.2       
   Component:  Runtime System  |      Version:  6.13         
    Keywords:                  |   Difficulty:               
          Os:  Solaris         |     Testcase:               
Architecture:  sparc           |      Failure:  Runtime crash
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Comment(by benl):

 The same program works fine on x86/Linux.

 Another DPH benchmark `sumsq` crashes about 1 time in 20 on the
 SPARC/Solaris, so it does sound like a race condition of some kind. This
 wikipedia page http://en.wikipedia.org/wiki/Memory_ordering suggests that
 SPARC TSO and x86 memory ordering should be similar, and if that's true
 then I don't know why SPARC is crashing and x86 isn't. I'll do some
 digging.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/3875#comment:4>
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