[GHC] #14802: panic! (the 'impossible' happened)

[GHC]

#14802: panic! (the 'impossible' happened)
-------------------------------------+-------------------------------------
        Reporter:  Ebanflo           |                Owner:  (none)
            Type:  bug               |               Status:  infoneeded
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.2
  (Debugging)                        |
      Resolution:                    |             Keywords:
Operating System:  Linux             |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by hsyl20):

 You can use `stack` to easily launch a GHCi session for different GHC
 compiler versions:

 {{{
 stack --resolver=ghc-8.0.1 repl --package vector --package primitive
 stack --resolver=ghc-8.0.2 repl --package vector --package primitive
 stack --resolver=ghc-8.2.2 repl --package vector --package primitive
 }}}

 Otherwise use `which ghci` to check which `ghci` is being used or use `ghc
 --interactive` instead of `ghci` (as `ghc -v` shows the expected version,
 it should work).

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14802#comment:3>
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