[GHC] #12847: ghci -fobject-code -O2 doesn't do the same optimisations as ghc --make -O2

[GHC]

#12847: ghci -fobject-code -O2 doesn't do the same optimisations as ghc --make -O2
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        Reporter:  nh2               |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.1
      Resolution:                    |             Keywords:
Operating System:  Other             |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by nh2):

 Replying to [comment:1 rwbarton]:
 > you seem to be invoking `ghci` and then running `:set -fforce-recomp
 -fobject-code -O2 -v`

 I am.

 Your guess seems right, if I start ghci on the command line with these
 flags, it's just as slow as ghc.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12847#comment:2>
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