[GHC] #11525: Using a dummy typechecker plugin causes an ambiguity check error

[GHC]

#11525: Using a dummy typechecker plugin causes an ambiguity check error
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        Reporter:  jme               |                Owner:  darchon
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.2.1
       Component:  Compiler (Type    |              Version:  8.0.1-rc1
  checker)                           |             Keywords:
      Resolution:                    |  UndecidableSuperClasses, plugin
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  GHC rejects       |  Unknown/Multiple
  valid program                      |            Test Case:  T11525
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |  https://phabricator.haskell.org/D3105
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Changes (by darchon):

 * differential:  D3105 => https://phabricator.haskell.org/D3105


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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11525#comment:9>
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