[GHC] #15485: GHC uses 300% CPU when calling into blocking C call

[GHC]

#15485: GHC uses 300% CPU when calling into blocking C call
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        Reporter:  oconnore          |                Owner:  (none)
            Type:  bug               |               Status:  infoneeded
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Runtime System    |              Version:  8.4.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:  x86_64
                                     |  (amd64)
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by osa1):

 * status:  new => infoneeded


Comment:

 oconnore, would it be possible for you to provide a reproducer? I looked
 at the /r/haskell thread but I still have no idea how to reproduce this. A
 cabal package would work (please avoid stack if possible, it adds extra
 friction).

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15485#comment:2>
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