[GHC] #7970: Thread GC frees roots before thread actually finishes

[GHC]

#7970: Thread GC frees roots before thread actually finishes
---------------------------------+------------------------------------------
    Reporter:  joeyadams         |       Owner:  simonmar        
        Type:  bug               |      Status:  new             
    Priority:  high              |   Milestone:  7.8.1           
   Component:  Runtime System    |     Version:  7.6.3           
    Keywords:                    |          Os:  Unknown/Multiple
Architecture:  Unknown/Multiple  |     Failure:  Runtime crash   
  Difficulty:  Unknown           |    Testcase:                  
   Blockedby:                    |    Blocking:                  
     Related:  7170              |  
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Changes (by simonmar):

  * owner:  => simonmar
  * difficulty:  => Unknown
  * priority:  normal => high
  * milestone:  => 7.8.1


Comment:

 This is technically not a bug - the thread is unreachable when it is
 deadlocked, and so is the weak pointer.

 However, we have had a feature request in the past to change this
 behaviour, and I can see that in this case it is less than useful.  I'll
 look into reversing the order so that we establish the reachability of
 threads before weak pointers.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7970#comment:1>
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