[GHC] #4001: Implement an atomic readMVar

[GHC]

#4001: Implement an atomic readMVar
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        Reporter:           |            Owner:  ezyang
  simonmar                  |           Status:  closed
            Type:  task     |        Milestone:  7.6.2
        Priority:  low      |          Version:  6.12.2
       Component:  Runtime  |         Keywords:
  System                    |     Architecture:  Unknown/Multiple
      Resolution:  fixed    |       Difficulty:  Moderate (less than a day)
Operating System:           |       Blocked By:
  Unknown/Multiple          |  Related Tickets:
 Type of failure:           |
  None/Unknown              |
       Test Case:           |
        Blocking:           |
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Comment (by ezyang):

 {{{
 commit db8d4a345ef77bc6832e9496e0ba38c8e36cadff
 Author: Edward Z. Yang <ezyang at mit.edu>
 Date:   Wed Jul 10 13:32:15 2013 -0700

     Implement tryAtomicReadMVar#.

     Signed-off-by: Edward Z. Yang <ezyang at mit.edu>
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/4001#comment:28>
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