[GHC] #12911: Levity polymorphism check eliminates non-levity-polymorphic data constructor

[GHC]

#12911: Levity polymorphism check eliminates non-levity-polymorphic data
constructor
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        Reporter:  goldfire          |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.1
      Resolution:                    |             Keywords:
                                     |  LevityPolymorphism
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by simonpj):

 Yes, that's over-restrictive; when Richard gets around to implementing the
 paper (which is very much on his radar I think) it'll be fixed!

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12911#comment:2>
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