[GHC] #15318: Core Lint error involving newtype family instances with wrappers

[GHC]

#15318: Core Lint error involving newtype family instances with wrappers
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        Reporter:  RyanGlScott       |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler (Type    |              Version:  8.4.3
  checker)                           |
      Resolution:                    |             Keywords:  TypeFamilies
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  crash or panic                     |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D4902
       Wiki Page:                    |
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Changes (by mpickering):

 * differential:   => Phab:D4902


Comment:

 See https://phabricator.haskell.org/D4902

 Which is Richard's fix cherry-picked.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15318#comment:1>
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