[GHC] #14339: GHC 8.2.1 regression when combining GND with TypeError (solveDerivEqns: probable loop)

[GHC]

#14339: GHC 8.2.1 regression when combining GND with TypeError (solveDerivEqns:
probable loop)
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        Reporter:  RyanGlScott       |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:  8.4.1
       Component:  Compiler (Type    |              Version:  8.2.1
  checker)                           |             Keywords:  deriving,
      Resolution:                    |  CustomTypeErrors
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  crash or panic                     |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by RyanGlScott):

 This is technically my fault, since this regression first started
 happening in 639e702b6129f501c539b158b982ed8489e3d09c (`Refactor
 DeriveAnyClass's instance context inference`). That being said, I don't
 have any inclination as to what part of that patch tickles this panic.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14339#comment:1>
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