[GHC] #12201: Wrong instance selection with overlapping instance in a superclass

[GHC]

#12201: Wrong instance selection with overlapping instance in a superclass
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        Reporter:  kanetw            |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler (Type    |              Version:  8.0.1
  checker)                           |
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by kanetw):

 That sounds like the right thing to do. It feels a bit unpleasant from an
 aesthetics perspective, but I can't really think of a better solution.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12201#comment:6>
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