[GHC] #10577: Use empty cases where appropriate when deriving instances for empty types

[GHC]

#10577: Use empty cases where appropriate when deriving instances for empty types
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        Reporter:  rwbarton          |                Owner:  (none)
            Type:  bug               |               Status:  patch
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  7.11
      Resolution:                    |             Keywords:  deriving
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #13117, #7401     |  Differential Rev(s):  Phab:D4047
       Wiki Page:                    |
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Comment (by mpickering):

 I still think there should be a "few examples where folks tied knots with
 fixed points to get inhabitants of Void" seeing as that is the primary
 motivation for this implementation. They are good for tests and notes even
 though I accept I will find them dubious.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10577#comment:8>
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