[GHC] #9407: Program produces different output when compiled with -O

[GHC]

#9407: Program produces different output when compiled with -O
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              Reporter:  arotenberg  |            Owner:
                  Type:  bug         |           Status:  new
              Priority:  normal      |        Milestone:
             Component:  Compiler    |          Version:  7.8.3
            Resolution:              |         Keywords:
      Operating System:  Windows     |     Architecture:  x86_64 (amd64)
       Type of failure:  Incorrect   |       Difficulty:  Unknown
  result at runtime                  |       Blocked By:
             Test Case:              |  Related Tickets:
              Blocking:              |
Differential Revisions:              |
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Comment (by arotenberg):

 I have verified that I can consistently recreate the issue on another
 computer running Windows 7 x86-64 with GHC 7.8.3. I believe the issue was
 also present in 7.8.2, since I upgraded to 7.8.3 with the express purpose
 of seeing if this issue had been fixed.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9407#comment:4>
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