[GHC] #14535: ghc: panic! (the 'impossible' happened) (GHC version 8.2.1 for x86_64-apple-darwin): stack depth overflow

[GHC]

#14535: ghc: panic! (the 'impossible' happened)   (GHC version 8.2.1 for x86_64
-apple-darwin):  stack depth overflow
-------------------------------------+-------------------------------------
        Reporter:  iTotallyExist     |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:
       Component:  Compiler          |              Version:  8.2.1
      Resolution:                    |             Keywords:  panic! stack
                                     |  depth overflow
Operating System:  MacOS X           |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  GHCi crash        |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
-------------------------------------+-------------------------------------

Comment (by mpickering):

 What is the actual compiler error?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14535#comment:4>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler