[GHC] #7684: cgrun071 segfaults

[GHC]

#7684: cgrun071 segfaults
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        Reporter:  tibbe          |            Owner:
            Type:  bug            |           Status:  patch
        Priority:  normal         |        Milestone:  7.8.1
       Component:  Compiler       |          Version:  7.7
      Resolution:                 |         Keywords:
Operating System:  MacOS X        |     Architecture:  x86_64 (amd64)
 Type of failure:  Runtime crash  |       Difficulty:  Unknown
       Test Case:  cgrun071       |       Blocked By:
        Blocking:                 |  Related Tickets:
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Comment (by simonmar):

 The patch is very likely to be papering over the problem rather than
 fixing it.  While the primop does take a Word# (because there's no
 `Word8#`), the MachOp `MO_PopCnt` really does take an 8-bit value when it
 is generated by the 8-bit version of the primop.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/7684#comment:40>
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