Re: [GHC] #10100: Bogus "redundant constraint" warning with functional dependencies

20 Feb 2015

      #10100: Bogus "redundant constraint" warning with functional dependencies
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        Reporter:  jstolarek         |                   Owner:  simonpj
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:  7.10.1
       Component:  Compiler          |                 Version:  7.11
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:
 Type of failure:  None/Unknown      |  Unknown/Multiple
      Blocked By:                    |               Test Case:
 Related Tickets:                    |                Blocking:
                                     |  Differential Revisions:
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Comment (by Simon Peyton Jones ):

 In [changeset:"10fab31211961c9200d230556ec7742e07a6c831/ghc"]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="10fab31211961c9200d230556ec7742e07a6c831"
 Don't report instance constraints with fundeps as redundant

 More subtlety due to functional dependencies.
 Note [Redundant constraints in instance decls] in TcErrors.

 Fixes Trac #10100.
 }}}

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Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10100#comment:3
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