[GHC] #2910: throwTo can block indefinitely when target thread finishes with exceptions blocked

[GHC]

#2910: throwTo can block indefinitely when target thread finishes with exceptions
blocked
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    Reporter:  int-e             |        Owner:  igloo           
        Type:  merge             |       Status:  new             
    Priority:  normal            |    Milestone:  6.10.2          
   Component:  Runtime System    |      Version:  6.10.1          
    Severity:  normal            |   Resolution:                  
    Keywords:                    |   Difficulty:  Easy (1 hr)     
    Testcase:                    |           Os:  Unknown/Multiple
Architecture:  Unknown/Multiple  |  
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Comment (by int-e):

 As the patches I just attached suggest, this race is not completely fixed.
 (I'm pretty certain - Conal's TestRace program locks up without the first
 patch, but works fine so far with it. I also have a modified version that
 logs thread creation and throwTo and shows the program lock up with all
 threads finished except the main thread, which is blocked on an
 exception.)

 The second patch contains changes unrelated to this bug which I'm not 100%
 certain about - but they felt necessary.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/2910#comment:3>
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