[GHC] #15586: Compilation panic! (the 'impossible' happened)

[GHC]

#15586: Compilation panic! (the 'impossible' happened)
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        Reporter:  subaruru          |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.4.3
      Resolution:                    |             Keywords:
Operating System:  Linux             |         Architecture:  x86_64
 Type of failure:  Compile-time      |  (amd64)
  crash or panic                     |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by osa1):

 Unfortunately there's no easy way to test this package with newer GHCs as
 some
 of its dependencies (zippers, probably lens too) use custom Setup.hs which
 requires building Cabal which doesn't build with newer GHCs (tested with
 8.6.1
 beta and HEAD).

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15586#comment:2>
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