[GHC] #14690: Pattern match failure in GHCi with :steplocal

[GHC]

#14690: Pattern match failure in GHCi with :steplocal
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        Reporter:  Philonous     |                Owner:  (none)
            Type:  bug           |               Status:  new
        Priority:  normal        |            Milestone:
       Component:  GHCi          |              Version:  8.2.2
      Resolution:                |             Keywords:  debugger
Operating System:  Linux         |         Architecture:  x86_64 (amd64)
 Type of failure:  None/Unknown  |            Test Case:
      Blocked By:                |             Blocking:
 Related Tickets:                |  Differential Rev(s):
       Wiki Page:                |
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Comment (by RolandSenn):

 Up to GHC 8.4.4 we get the ''Pattern match failure'' message as shown in
 the ticket. \\
 With GHC 8.6.1 and higher we get a ''panic'' message:


 {{{
 [<unknown>] Prelude> :steplocal
 <interactive>: panic! (the 'impossible' happened)
   (GHC version 8.6.1 for x86_64-unknown-linux):
         enclosingTickSpan UnhelpfulSpan
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14690#comment:3>
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