[GHC] #4485: Per-class incoherence, and solve incoherent instances last

[GHC]

#4485: Per-class incoherence, and solve incoherent instances last
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    Reporter:  JeremyShaw        |        Owner:                                 
        Type:  bug               |       Status:  new                            
    Priority:  normal            |    Milestone:  7.2.1                          
   Component:  Compiler          |      Version:  7.0.1 RC1                      
    Keywords:                    |     Testcase:  indexed-types/should_fail/T4485
   Blockedby:                    |   Difficulty:                                 
          Os:  Unknown/Multiple  |     Blocking:                                 
Architecture:  Unknown/Multiple  |      Failure:  GHC rejects valid program      
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Changes (by simonpj):

  * testcase:  => indexed-types/should_fail/T4485


Comment:

 Added a regression test for the instance-overlap crash.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/4485#comment:9>
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