[GHC] #9279: Local wrapper function remains in final program; result = extra closure allocation

[GHC]

#9279: Local wrapper function remains in final program; result = extra closure
allocation
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        Reporter:  simonmar          |                Owner:  simonpj
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  7.8.2
      Resolution:                    |             Keywords:  LateLamLift
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 sgraf):

 OK, this diff in isolation provokes Core Lint errors everywhere:

 {{{
 *** Core Lint errors : in result of Worker Wrapper binds ***
 <no location info>: warning:
     [RHS of ww_scA1 :: Array# b_sczT]
     The type of this binder doesn't match the type of its RHS: ww_scA1
     Binder's type: Array# b_sczT
 }}}

 So, it's pretty clear we would have to add an additional field to
 `MachNullAddr` (`MachNull` would probably be more appropriate) for the
 type it represents, similar to `LitNumber`.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9279#comment:16>
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