[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:  new
        Priority:  normal            |        Milestone:
       Component:  Compiler          |          Version:  7.7
      Resolution:                    |         Keywords:
Operating System:  Unknown/Multiple  |     Architecture:  Unknown/Multiple
 Type of failure:  Other             |       Difficulty:  Unknown
       Test Case:                    |       Blocked By:
        Blocking:                    |  Related Tickets:
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Comment (by goldfire):

 This is actually a bug in core lint, not in the code generation -- core
 lint doesn't consider the possibility of `(~R#)` arguments to functions,
 but some optimizations produce these. Patch on the way...

 If this is holding you up at the moment, just delete line 404 of
 !CoreLint.lhs "`       ; checkRole co Nominal role`".

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8138#comment:1>
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