[GHC] #12466: Typechecker regression: Inaccessible code in a type expected by the context

[GHC]

#12466: Typechecker regression: Inaccessible code in a type expected by the context
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        Reporter:  RyanGlScott       |                Owner:
            Type:  bug               |               Status:  new
        Priority:  highest           |            Milestone:  8.0.2
       Component:  Compiler (Type    |              Version:  8.1
  checker)                           |
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  GHC rejects       |  Unknown/Multiple
  valid program                      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by goldfire):

 Urgh. It seems I was even more confused than I realized in comment:14.
 Quite likely every word I've posted (hopefully not including these) is
 simply utter nonsense. Deep apologies. The confusion is entirely my own
 fault and not the result of anyone else's miscommunication.
 Let me try again.

 Yes, this is a bug. We should indeed accept the original program without
 any warnings.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12466#comment:19>
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