[GHC] #8314: ASSERTion at TcMType:809 fails on test polykinds/T6068

[GHC]

#8314: ASSERTion at TcMType:809 fails on test polykinds/T6068
-------------------------------------+------------------------------------
        Reporter:  goldfire          |            Owner:
            Type:  bug               |           Status:  new
        Priority:  normal            |        Milestone:
       Component:  Compiler          |          Version:  7.7
      Resolution:                    |         Keywords:
Operating System:  Unknown/Multiple  |     Architecture:  Unknown/Multiple
 Type of failure:  None/Unknown      |       Difficulty:  Unknown
       Test Case:                    |       Blocked By:
        Blocking:                    |  Related Tickets:  8129
-------------------------------------+------------------------------------
Changes (by adamgundry):

 * cc: adam.gundry@… (added)
 * related:   => 8129


Comment:

 I've tracked this down a bit (see comments to #8129). The problem seems to
 have been introduced in  e365d4963f1061878269502f256b4a56ca273a78. I don't
 know enough about the constraint solver to be sure of the right fix,
 however.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8314#comment:1>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler