[GHC] #9968: DeriveAnyClass fails on multi-parameter type classes

[GHC]

#9968: DeriveAnyClass fails on multi-parameter type classes
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        Reporter:  goldfire          |                   Owner:  dreixel
            Type:  bug               |                  Status:  new
        Priority:  high              |               Milestone:  7.10.1
       Component:  Compiler          |                 Version:  7.10.1-rc1
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:
 Type of failure:  None/Unknown      |  Unknown/Multiple
      Blocked By:                    |               Test Case:
 Related Tickets:  #9821             |                Blocking:
                                     |  Differential Revisions:
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Comment (by dreixel):

 Simon, could you give me some help with this? I was hoping it would be
 easy to just reuse the infrastructure for newtype deriving here. Should I
 follow the structure of the `EarlyDerivSpec` generated by the first branch
 of `mkNewTypeEqn`?

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9968#comment:4>
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