[GHC] #7684: cgrun071 segfaults

[GHC]

#7684: cgrun071 segfaults
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        Reporter:  tibbe          |            Owner:  leroux
            Type:  bug            |           Status:  new
        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 tibbe):

 I'm confused. The test isn't compiled with -msse42 and thus the popcnt
 instruction should never be omitted (check the output assembly to make
 sure) so it seems more likely that the failure has to do with narrowing.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/7684#comment:20>
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