[GHC] #12506: Compile time regression in GHC 8.

[GHC]

#12506: Compile time regression in GHC 8.
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        Reporter:  deech             |                Owner:  bgamari
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:  8.4.1
       Component:  Compiler          |              Version:  8.0.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by simonpj):

 > The problem persists with D4394 applied

 I was not expecting that D4394 would help. The problem here is that the
 coercions are too big.  The encouraging news is that 7.10.3 didn't have
 that problem, so it's an existence proof that we don't ''need'' big
 coercions.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12506#comment:31>
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