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

[GHC]

#15290: QuantifiedConstraints: panic "addTcEvBind NoEvBindsVar"
-------------------------------------+-------------------------------------
        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{,a,b},
                                     |  deriving/should_compile/T15290{c,d},
                                     |  deriving/should_compile/T14883
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D4895
       Wiki Page:                    |
-------------------------------------+-------------------------------------
Changes (by RyanGlScott):

 * testcase:  quantified-constraints/T15290, T15290a =>
     quantified-constraints/T15290{,a,b},
     deriving/should_compile/T15290{c,d}, deriving/should_compile/T14883
 * blocking:  9123 =>


Comment:

 With the commit in comment:37, that should take care of business.

 As far as which commits to merge, my understanding is that you would need
 everything mentioned in this ticket, which encompasses:

 * 32eb41994f7448caf5fb6b06ed0678d79d029deb
 * 9fc40c733ba8822a04bd92883801b214dee099ca
 * 261dd83cacec71edd551e9c581d05285c9ea3226
 * 132273f34e394bf7e900d0c15e01e91edd711890

 Does that sound right?

 Also, I apologize in advance to Ben :)

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15290#comment:38>
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