[GHC] #15024: ghc: please switch to llvm-toolchain-6.0

[GHC]

#15024: ghc: please switch to llvm-toolchain-6.0
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        Reporter:  LocutusOfBorg     |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.2.2
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by bgamari):

 I've validated against LLVM 6 on amd64/Linux
 (https://circleci.com/gh/ghc/ghc/5984). I observed numerous segmentation
 faulting tests in the `ext-interp` way, although I don't believe the
 situation is much different from LLVM 5 (e.g.
 https://circleci.com/gh/ghc/ghc/5991)

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15024#comment:4>
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