[GHC] #10317: Event manager: Multishot registrations only fire once

[GHC]

#10317: Event manager: Multishot registrations only fire once
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        Reporter:  bgamari           |                   Owner:
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:  7.10.2
       Component:  Compiler          |                 Version:  7.10.1
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:
 Type of failure:  Incorrect result  |  Unknown/Multiple
  at runtime                         |               Test Case:
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:  D849
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Changes (by bgamari):

 * differential:   => D849


Comment:

 I've written a pair of tests exercising both failure modes,
 https://github.com/bgamari/event-manager-tests

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10317#comment:3>
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