[GHC] #15757: Coercion Variable Almost Devoid Checking in ForAllCo

[GHC]

#15757: Coercion Variable Almost Devoid Checking in ForAllCo
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        Reporter:  ningning          |                Owner:  ningning
            Type:  task              |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #15497            |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by simonpj):

 Interesting.  Before we are done with coercion quantification, it'd be
 good to update the core-spec.tex document to cover it; with some
 accompanying text to explain subtle points like this one.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15757#comment:2>
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