[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:
       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 tdammers):

 It turns out that `Main.hs` produces about 2.8G of Core. This part seems
 to be the culprit:

 {{{
 -- RHS size: {terms: 6,002,
               types: 8,003,
               coercions: 1,415,000,
               joins: 0/0}
 main :: IO ()
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12506#comment:21>
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