[GHC] #15368: Type families, holes and -fdefer-type-errors may cause 'opt_univ fell into a hole' panic

[GHC]

#15368: Type families, holes and -fdefer-type-errors may cause 'opt_univ fell into
a hole' panic
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        Reporter:  dramforever       |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.4.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  Compile-time      |            Test Case:
  crash or panic                     |  typecheck/should_compile/T15368
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by bgamari):

 * testcase:   => typecheck/should_compile/T15368


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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15368#comment:3>
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