[GHC] #4820: "Invalid object in isRetainer" when doing retainer profiling in GHC 7 branch

[GHC]

#4820: "Invalid object in isRetainer" when doing retainer profiling in GHC 7
branch
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        Reporter:  dleuschner     |                Owner:  (none)
            Type:  bug            |               Status:  infoneeded
        Priority:  highest        |            Milestone:  8.4.1
       Component:  Profiling      |              Version:  8.0.1
      Resolution:                 |             Keywords:
Operating System:  MacOS X        |         Architecture:  x86_64 (amd64)
 Type of failure:  Runtime crash  |            Test Case:
      Blocked By:                 |             Blocking:
 Related Tickets:  #11978         |  Differential Rev(s):
       Wiki Page:                 |
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Comment (by bgamari):

 Note that ​Phab:D3967 may be relevant to some of the issues reported
 above.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/4820#comment:13>
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