[GHC] #12957: In a record-update construct:ghc-stage2: panic! (the 'impossible' happened)

[GHC]

#12957: In a record-update construct:ghc-stage2: panic! (the 'impossible' happened)
-------------------------------------+-------------------------------------
        Reporter:  niteria           |                Owner:  mpickering
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D3065,
       Wiki Page:                    |  Phab:D3064
-------------------------------------+-------------------------------------

Comment (by Ben Gamari <ben@…>):

 In [changeset:"68cbe52fd3ae618a9778e79bf6a9806bab21aff2/ghc"
 68cbe52f/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="68cbe52fd3ae618a9778e79bf6a9806bab21aff2"
 Don't panic when printing match with RecUpd context

 Reviewers: bgamari, austin

 Reviewed By: bgamari

 Subscribers: thomie

 Differential Revision: https://phabricator.haskell.org/D3065

 GHC Trac Issues: #12957
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12957#comment:10>
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