[GHC] #11762: GHC 8 superclass chain constraint regression

[GHC]

#11762: GHC 8 superclass chain constraint regression
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        Reporter:  _deepfire         |                Owner:
            Type:  bug               |               Status:  closed
        Priority:  highest           |            Milestone:  8.0.1
       Component:  Compiler (Type    |              Version:  8.0.1-rc2
  checker)                           |
      Resolution:  duplicate         |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  GHC rejects       |  Unknown/Multiple
  valid program                      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #11427            |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"933abfa7ec88bd91e60a62e51bb2f9a068d379f1/ghc"
 933abfa7/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="933abfa7ec88bd91e60a62e51bb2f9a068d379f1"
 rel-notes: Add note about UndecidableSuperClasses and #11762

 Test Plan: Read it

 Reviewers: austin, kosmikus

 Reviewed By: kosmikus

 Subscribers: thomie

 Differential Revision: https://phabricator.haskell.org/D2111

 GHC Trac Issues: #11318, #11762
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11762#comment:7>
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