[GHC] #14777: panic when using a function defined in terms of `error`

[GHC]

#14777: panic when using a function defined in terms of `error`
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        Reporter:  zilinc            |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.2.2
      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 zilinc):

 Replying to [comment:11 tdammers]:
 > I tried to reproduce this on GHC 8.2.1, but it builds cleanly, both with
 `__impossible` and `undefined`. I'm using the current `master` branch
 though, because the specified commit doesn't seem to exist in any of the
 exposed branches anymore.

 The commit is still there. But I totally believe that you could not
 reproduce it on an arbitrary commit, otherwise it would be easier to
 figure out what crashed the compiler.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14777#comment:12>
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