[GHC] #11370: Redundant superclass warnings being included in -Wall destroys the "3 Release Policy"

[GHC]

#11370: Redundant superclass warnings being included in -Wall destroys the "3
Release Policy"
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        Reporter:  ekmett            |                Owner:  bgamari
            Type:  bug               |               Status:  new
        Priority:  highest           |            Milestone:  8.0.1
       Component:  Compiler (Type    |              Version:  7.10.3
  checker)                           |
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #11369, #11429    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"8e9a87025f954a2704850bc71cb497f768d5d595/ghc" 8e9a870/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="8e9a87025f954a2704850bc71cb497f768d5d595"
 Remove -Wredundant-superclasses from standard warnings

 It is impossible to write warning-free code under the three-release
 policy with this flag enabled by default. See #11370 for details.
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11370#comment:20>
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