[GHC] #11665: Recent master fails to build attoparsec-0.13.0.1 with core lint failure

[GHC]

#11665: Recent master fails to build attoparsec-0.13.0.1 with core lint failure
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           Reporter:  anton.dessiatov  |             Owner:
               Type:  bug              |            Status:  new
           Priority:  normal           |         Milestone:
          Component:  Compiler         |           Version:  8.1
           Keywords:                   |  Operating System:  Linux
       Architecture:  x86_64 (amd64)   |   Type of failure:  None/Unknown
          Test Case:                   |        Blocked By:
           Blocking:                   |   Related Tickets:  11664
Differential Rev(s):                   |         Wiki Page:
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 You might also like to see #11664 for some history.

 I have tried using current `master`
 57b4c5524fcbf02f61dfc8d9395906dc7f50f048 to build current
 `attoparsec-0.13.0.1` on Ubuntu Linux 15.10 x86_64. The build fails with
 Core Lint error

 {{{
 <no location info>: warning:
     In the type ‘Buffer
                  -> Pos -> More -> a_aOwS -> IResult Text r_aOwT’
     @ a_aOwS is out of scope
 }}}

 Attached comes full output of `cabal install attoparsec --with-ghc=<path-
 to-ghc> --verbose --ghc-options -dcore-lint`. The output is huge (57k
 lines) so I gzipped it.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11665>
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