[GHC] #13002: :set -O does not work in .ghci file

[GHC]

#13002: :set -O does not work in .ghci file
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        Reporter:  George            |                Owner:  (none)
            Type:  bug               |               Status:  closed
        Priority:  normal            |            Milestone:  8.0.3
       Component:  GHCi              |              Version:  8.0.1
      Resolution:  worksforme        |             Keywords:
                                     |  RecompilationCheck
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Runtime           |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by dfeuer):

 That is, GHC's processing of its own command line could affect GC timings
 in some tiny way that is enough to lead to the difference you experienced.
 Just to make really sure, I turned on `-ddump-simpl` and saw that the core
 produced when loading the test file had all the signs of having been
 optimized (e.g., strictness annotations, unfoldings, and worker/wrapper
 pairs).

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13002#comment:9>
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