[GHC] #10675: GHC does not check the functional dependency consistency condition correctly

[GHC]

#10675: GHC does not check the functional dependency consistency condition
correctly
-------------------------------------+-------------------------------------
        Reporter:  simonpj           |                   Owner:
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:
       Component:  Compiler          |                 Version:  7.10.1
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |               Test Case:
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:
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Comment (by Simon Peyton Jones <simonpj@…>):

 In [changeset:"d53d80890f2762b78071f5d53c88dc9e6c0ca72e/ghc"
 d53d8089/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="d53d80890f2762b78071f5d53c88dc9e6c0ca72e"
 Refactoring around FunDeps

 This refactoring was triggered by Trac #10675.

 We were using 'improveClsFD' (previously called 'checkClsFD') for
 both
   * Improvement: improving a constraint against top-level instances
   * Consistency: checking when two top-level instances are
     consistent

 Using the same code for both seemed attractive at the time, but
 it's just too complicated.  So I've split it:
  * Improvement: improveClsFD
  * Consistency: checkFunDeps

 Much clearer now!
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10675#comment:5>
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