[GHC] #15380: Infinite typechecker loop in GHC 8.6

[GHC]

#15380: Infinite typechecker loop in GHC 8.6
-------------------------------------+-------------------------------------
        Reporter:  RyanGlScott       |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:  8.6.1
       Component:  Compiler (Type    |              Version:  8.5
  checker)                           |             Keywords:  TypeInType,
      Resolution:                    |  TypeFamilies
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by RyanGlScott):

 * cc: goldfire (added)
 * version:  8.4.3 => 8.5


Comment:

 This regression was introduced in commit
 faec8d358985e5d0bf363bd96f23fe76c9e281f7 (`Track type variable scope more
 carefully.`).

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15380#comment:1>
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