[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 now also verified that this problem does ''not'' occur on 32-bit
 Windows nor when using 32-bit GHC on 64-bit Windows. But you should be
 able to reproduce it if you use 64-bit Windows and 64-bit GHC 7.8.3.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9407#comment:5>
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