[GHC] #8138: Core lint fails with error "Role incompatibility: expected N, got R"

[GHC]

#8138: Core lint fails with error "Role incompatibility: expected N, got R"
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        Reporter:  gmainland         |            Owner:
            Type:  bug               |           Status:  merge
        Priority:  normal            |        Milestone:
       Component:  Compiler          |          Version:  7.7
      Resolution:                    |         Keywords:
Operating System:  Unknown/Multiple  |     Architecture:  Unknown/Multiple
 Type of failure:  Other             |       Difficulty:  Easy (less than 1
       Test Case:                    |  hour)
  deriving/should_compile/T8138      |       Blocked By:
        Blocking:                    |  Related Tickets:
-------------------------------------+-------------------------------------
Changes (by goldfire):

 * status:  new => merge
 * difficulty:  Unknown => Easy (less than 1 hour)
 * testcase:   => deriving/should_compile/T8138


Comment:

 Thanks for reporting this!

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8138#comment:4>
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