[GHC] #9646: Simplifer non-determinism leading to 8 fold difference in run time performance

[GHC]

#9646: Simplifer non-determinism leading to 8 fold difference in run time
performance
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        Reporter:  erikd             |                   Owner:
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:  7.10.3
       Component:  Compiler          |                 Version:  7.8.3
      Resolution:                    |                Keywords:
Operating System:  Linux             |            Architecture:  x86_64
 Type of failure:  Runtime           |  (amd64)
  performance bug                    |               Test Case:
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:
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Comment (by simonpj):

 > Moving to 7.10.3 - would be nice to fix.

 I don't understand. It's apparently fixed in 7.9 and so should be fixed in
 7.10.2, right?  What we need is a test case so we will know if it
 regresses.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9646#comment:17>
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