[GHC] #5654: Profiling semantics bug

[GHC]

#5654: Profiling semantics bug
-------------------------------------+-------------------------------------
              Reporter:  simonmar    |            Owner:  simonmar
                  Type:  bug         |           Status:  infoneeded
              Priority:  low         |        Milestone:  7.10.1
             Component:  Profiling   |          Version:  7.2.1
            Resolution:              |         Keywords:
      Operating System:              |     Architecture:  Unknown/Multiple
  Unknown/Multiple                   |       Difficulty:  Unknown
       Type of failure:              |       Blocked By:
  None/Unknown                       |  Related Tickets:
             Test Case:              |
  profiling/should_run/scc004        |
              Blocking:              |
Differential Revisions:              |
-------------------------------------+-------------------------------------
Changes (by thomie):

 * status:  new => infoneeded
 * difficulty:   => Unknown


Comment:

 The results with HEAD are both different from "what we want" and "what we
 get". What are we aiming for precisely?

 `ghc-7.9.20141125 -prof -fforce-recomp test.hs; ./test +RTS -p`
 {{{
   MAIN        MAIN                     43           0    0.0   22.2
 0.0  100.0
    CAF        Main                     85           0    0.0    0.1
 0.0    0.1
     g         Main                     87           1    0.0    0.0
 0.0    0.0
     f         Main                     86           1    0.0    0.0
 0.0    0.0
 }}}

 And with `-O2`:
 {{{
   MAIN        MAIN                     43           0    0.0   22.2
 0.0  100.0
    CAF        Main                     85           0    0.0    0.1
 0.0    0.1
     g         Main                     87           1    0.0    0.0
 0.0    0.0
     f         Main                     86           1    0.0    0.0
 0.0    0.0
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/5654#comment:5>
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