[GHC] #14605: Core Lint error

[GHC]

#14605: Core Lint error
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        Reporter:  Iceland_jack      |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.2.2
      Resolution:                    |             Keywords:  TypeInType,
                                     |  DeferredTypeErrors
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #14584            |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by monoidal):

 Similar to #14584. The essence is the code that is generated via GND for
 `Comonad PAIR`, which I've reduced to:

 {{{
 {-# Language TypeApplications #-}
 {-# Language ImpredicativeTypes #-}

 import GHC.Prim (coerce)

 duplicate = coerce @(forall x. ()) @(forall x. x)
 }}}

 (though it's possible there are more factors causing the bug and I
 isolated only one of them)

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14605#comment:2>
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