[GHC] #15586: Compilation panic! (the 'impossible' happened)

[GHC]

#15586: Compilation panic! (the 'impossible' happened)
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        Reporter:  subaruru          |                Owner:  (none)
            Type:  bug               |               Status:  patch
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.4.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  crash or panic                     |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #15499            |  Differential Rev(s):  Phab:D5118
       Wiki Page:                    |
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Comment (by Krzysztof Gogolewski <krz.gogolewski@…>):

 In [changeset:"a3a1a17ba7ddbc40b093c732e7e3a916b9531eac/ghc"
 a3a1a17b/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="a3a1a17ba7ddbc40b093c732e7e3a916b9531eac"
 Add a test for Trac #15586

 Summary: The bug is already fixed in master.

 Test Plan: make test TEST=T15586

 Reviewers: bgamari, simonpj

 Reviewed By: simonpj

 Subscribers: rwbarton, carter

 GHC Trac Issues: #15586

 Differential Revision: https://phabricator.haskell.org/D5118
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15586#comment:6>
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