[GHC] #14619: Output value of program changes upon compiling with -O optimizations

[GHC]

#14619: Output value of program changes upon compiling with -O optimizations
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        Reporter:  sheaf             |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.2.2
      Resolution:                    |             Keywords:
Operating System:  Windows           |         Architecture:  x86_64
 Type of failure:  Incorrect result  |  (amd64)
  at runtime                         |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Phyx-):

 Guess it is Windows specific...

 {{{
 Tamar at Rage ~/g/l/p/t/T3994.run> ghc "bug.hs" -O2 -fforce-recomp; ./bug.exe
 [1 of 1] Compiling Main             ( bug.hs, bug.o )
 Linking bug.exe ...
 Just ((0.0,0.0,0.0),0.0)
 Just ((0.0,0.0,100.0),1.0)
 }}}

 {{{
 Tamar at Rage ~/g/l/p/t/T3994.run> ghc "bug.hs" -O2 -fforce-recomp -fno-
 worker-wrapper; ./bug.exe
 [1 of 1] Compiling Main             ( bug.hs, bug.o )
 Linking bug.exe ...
 Just ((0.0,0.0,100.0),1.0)
 Just ((0.0,0.0,100.0),1.0)
 }}}

 {{{
 Tamar at Rage ~/g/l/p/t/T3994.run> ~/ghc2/inplace/bin/ghc-stage2.exe
 "bug.hs" -O2 -fforce-recomp; ./bug.exe
 [1 of 1] Compiling Main             ( bug.hs, bug.o )
 Linking bug.exe ...
 Just ((0.0,0.0,100.0),1.0)
 Just ((0.0,0.0,100.0),1.0)
 }}}

 So it seems to work on HEAD also, but the 8.0.2 fails..

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14619#comment:7>
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