[GHC] #15398: GADT deriving Ord generates inaccessible code in a pattern with constructor.

[GHC]

#15398: GADT deriving Ord generates inaccessible code in a pattern with
constructor.
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        Reporter:  philderbeast      |                Owner:  (none)
            Type:  bug               |               Status:  patch
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.2.2
      Resolution:                    |             Keywords:  deriving,
                                     |  PatternMatchWarnings
Operating System:  MacOS X           |         Architecture:  x86_64
                                     |  (amd64)
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #8128 #8740       |  Differential Rev(s):  Phab:D4993
       Wiki Page:                    |
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Comment (by goldfire):

 If we really want to capture the environment in an implication, we could
 just store the `Env TcGblEnv TcLclEnv`, as retrieved by `getEnv`. We might
 want to do this in `CtLoc`, too, for similar reasons.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15398#comment:14>
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