[GHC] #8199: Get rid of HEAP_ALLOCED

[GHC]

#8199: Get rid of HEAP_ALLOCED
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        Reporter:  ezyang   |            Owner:  ezyang
            Type:  feature  |           Status:  new
  request                   |        Milestone:  7.10.1
        Priority:  normal   |          Version:  7.7
       Component:           |         Keywords:
  Compiler                  |     Architecture:  Unknown/Multiple
      Resolution:           |       Difficulty:  Project (more than a week)
Operating System:           |       Blocked By:
  Unknown/Multiple          |  Related Tickets:
 Type of failure:           |
  None/Unknown              |
       Test Case:           |
        Blocking:           |
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Comment (by ezyang):

 ghc-stage2 "slow down" was actually a spinlock deadlock due to me excising
 too much code from the old MBlock implementation. As a bonus, the last
 bullet point is fixed. Version 2: now with less deadlock!

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8199#comment:2>
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