[GHC] #2786: Blackhole loops are not detected and reported in GHCi

[GHC]

#2786: Blackhole loops are not detected and reported in GHCi
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    Reporter:  simonmar          |       Owner:                  
        Type:  bug               |      Status:  new             
    Priority:  normal            |   Milestone:  _|_             
   Component:  GHCi              |     Version:  6.8.3           
    Keywords:                    |          Os:  Unknown/Multiple
Architecture:  Unknown/Multiple  |     Failure:  None/Unknown    
  Difficulty:  Unknown           |    Testcase:                  
   Blockedby:                    |    Blocking:                  
     Related:                    |  
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Comment(by simonmar):

 I looked into this a bit today.  One problem is that now GHCi is
 dynamically linked, we always retain all CAFs (because we set `keepCAFs`
 to true).  This means that any loop that goes through a CAF won't be
 detected as a black hole, because the CAF is inherently live.

 I suspect this isn't the only reason that we don't get blackhole
 exceptions in GHC, though.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/2786#comment:4>
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