[GHC] #14932: DeriveAnyClass produces unjustifiably untouchable unification variables

[GHC]

#14932: DeriveAnyClass produces unjustifiably untouchable unification variables
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        Reporter:  RyanGlScott       |                Owner:  (none)
            Type:  bug               |               Status:  patch
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler (Type    |              Version:  8.4.1
  checker)                           |
      Resolution:                    |             Keywords:  deriving
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  GHC rejects       |  Unknown/Multiple
  valid program                      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #13272, #14933    |  Differential Rev(s):  Phab:D4507
       Wiki Page:                    |
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Comment (by Simon Peyton Jones <simonpj@…>):

 In [changeset:"71d50db1f511d7aee32e6b429cdb912fcf6071b0/ghc" 71d50db/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="71d50db1f511d7aee32e6b429cdb912fcf6071b0"
 Minor refactor and commments

 Minor refactor and comments, following Ryan's excellent DeriveAnyClass
 bug (Trac #14932)
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14932#comment:6>
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