[GHC] #13850: Incorrect function signature causes the impossible to happen

[GHC]

#13850: Incorrect function signature causes the impossible to happen
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        Reporter:  erikd             |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.2.1
       Component:  Compiler          |              Version:  8.2.1-rc2
      Resolution:                    |             Keywords:
Operating System:  Linux             |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  crash or panic                     |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by erikd):

 Just tried with git HEAD and that fails in the same way.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13850#comment:1>
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