[GHC] #15918: GHC panic from QuantifiedConstraints(?)

[GHC]

#15918: GHC panic from QuantifiedConstraints(?)
-------------------------------------+-------------------------------------
        Reporter:  Iceland_jack      |                Owner:  (none)
            Type:  bug               |               Status:  closed
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.6.2
      Resolution:  fixed             |             Keywords:
                                     |  QuantifiedConstraints
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:  quantified-
                                     |  constraints/T15918
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |  https://gitlab.haskell.org/ghc/ghc/merge_requests/489
-------------------------------------+-------------------------------------
Changes (by simonpj):

 * testcase:   => quantified-constraints/T15918
 * status:  patch => closed
 * resolution:   => fixed


Comment:

 Regression test landed in
 https://gitlab.haskell.org/ghc/ghc/commit/db039a4a10fc8fa9e03e6781d1c0dc33151beda6

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15918#comment:14>
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