[GHC] #15427: Calling hs_try_putmvar from an unsafe foreign call can cause the RTS to hang

[GHC]

#15427: Calling hs_try_putmvar from an unsafe foreign call can cause the RTS to
hang
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        Reporter:  syntheorem        |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.8.1
       Component:  Runtime System    |              Version:  8.4.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  Runtime crash     |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by simonmar):

 `hs_try_putmvar` is designed to be called without a Capability, I hadn't
 anticipated that someone might want to call it from an unsafe FFI call.
 What's your use case?

 We could definitely make this clearer in the docs, and perhaps make it
 fail in a better way.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15427#comment:3>
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