[GHC] #7696: Another kindFunResult panic

[GHC]

#7696: Another kindFunResult panic
-----------------------------+----------------------------------------------
Reporter:  nwf               |          Owner:                  
    Type:  bug               |         Status:  new             
Priority:  normal            |      Component:  Compiler        
 Version:  7.6.2             |       Keywords:                  
      Os:  Unknown/Multiple  |   Architecture:  Unknown/Multiple
 Failure:  None/Unknown      |      Blockedby:                  
Blocking:                    |        Related:                  
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Comment(by monoidal):

 There are two different issues here: one causes panic in HEAD, the other
 in 7.6.2.

 Panic in HEAD (7.6 correctly reports error):

 {{{
 f1 :: (m a, t m)
 f1 = undefined

 f2 :: ((), m ())
 f2 = f1
 }}}

 Panic in 7.6 (HEAD correctly reports error):

 {{{
 lift :: m a -> t m a
 lift = undefined

 k :: f (Either Int Int)
 k = lift
 }}}

 The second one is probably the same cause as #7368, which was left unfixed
 in 7.6.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7696#comment:1>
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