[GHC] #7978: Profiling broken

[GHC]

#7978: Profiling broken
--------------------------------------------+------------------------------
        Reporter:  gmainland                |            Owner:
            Type:  bug                      |           Status:  new
        Priority:  highest                  |        Milestone:  7.8.1
       Component:  Compiler                 |          Version:  7.7
      Resolution:                           |         Keywords:
Operating System:  Unknown/Multiple         |     Architecture:
 Type of failure:  GHC doesn't work at all  |  Unknown/Multiple
       Test Case:                           |       Difficulty:  Unknown
        Blocking:                           |       Blocked By:
                                            |  Related Tickets:
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Comment (by ezyang):

 I've further narrowed down the bug to how selectors are compiled:

 {{{
 --- a/compiler/codeGen/StgCmmBind.hs
 +++ b/compiler/codeGen/StgCmmBind.hs
 @@ -282,7 +282,7 @@ mkRhsClosure    dflags bndr _cc _bi
      cgRhsStdThunk bndr lf_info [StgVarArg the_fv]
    where
      lf_info               = mkSelectorLFInfo bndr offset_into_int
 -                                 (isUpdatable upd_flag)
 +                                 (isUpdatable Updatable)
      (_, _, params_w_offsets) = mkVirtConstrOffsets dflags (addIdReps
 params)
                                 -- Just want the layout
      maybe_offset          = assocMaybe params_w_offsets (NonVoid
 selectee)
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/7978#comment:14>
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