[GHC] #12785: GHC panic, TypeFamily in equality constraint

[GHC]

#12785: GHC panic, TypeFamily in equality constraint
-------------------------------------+-------------------------------------
        Reporter:  heisenbug         |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
-------------------------------------+-------------------------------------
Changes (by heisenbug):

 * Attachment "Tree.hs" added.


--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12785>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler