[GHC] #13603: Can't resolve levity polymorphic superclass

[GHC]

#13603: Can't resolve levity polymorphic superclass
-------------------------------------+-------------------------------------
        Reporter:  Iceland_jack      |                Owner:  (none)
            Type:  bug               |               Status:  patch
        Priority:  normal            |            Milestone:  8.2.1
       Component:  Compiler          |              Version:  8.0.1
      Resolution:                    |             Keywords:
                                     |  LevityPolymorphism, TypeInType
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D3489
       Wiki Page:                    |
-------------------------------------+-------------------------------------
Changes (by RyanGlScott):

 * status:  new => patch
 * differential:   => Phab:D3489
 * milestone:   => 8.2.1


Comment:

 It works in GHC 8.2 too! Commit b207b536ded40156f9adb168565ca78e1eef2c74
 (Generalize kind of the (->) tycon) was what fixed it. I've added a
 regression test in Phab:D3489.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13603#comment:2>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler