[GHC] #15290: QuantifiedConstraints: panic "addTcEvBind NoEvBindsVar"

[GHC]

#15290: QuantifiedConstraints: panic "addTcEvBind NoEvBindsVar"
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        Reporter:  goldfire          |                Owner:  (none)
            Type:  bug               |               Status:  merge
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.4.3
      Resolution:                    |             Keywords:
                                     |  QuantifiedConstraints
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:  quantified-
                                     |  constraints/T15290, T15290a
      Blocked By:                    |             Blocking:  9123
 Related Tickets:                    |  Differential Rev(s):  Phab:D4895
       Wiki Page:                    |
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Comment (by bgamari):

 I'm putting this in merge state since there are already a few patches that
 need to be backported. However, the issue here isn't quite fixed until
 Phab:D4895 is merged to `master`.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15290#comment:36>
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