[GHC] #13871: GHC panic in 8.2 only: typeIsTypeable(Coercion)

[GHC]

#13871: GHC panic in 8.2 only: typeIsTypeable(Coercion)
-------------------------------------+-------------------------------------
        Reporter:  RyanGlScott       |                Owner:  bgamari
            Type:  bug               |               Status:  patch
        Priority:  high              |            Milestone:  8.2.1
       Component:  Compiler (Type    |              Version:  8.2.1-rc2
  checker)                           |             Keywords:  TypeInType,
      Resolution:                    |  Typeable
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  Compile-time      |            Test Case:
  crash or panic                     |  typecheck/should_compile/T13871
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D3671,
       Wiki Page:                    |  Phab:D3672
-------------------------------------+-------------------------------------

Comment (by Ben Gamari <ben@…>):

 In [changeset:"134652542923e432bffb9fafe87893d785a17aae/ghc"
 13465254/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="134652542923e432bffb9fafe87893d785a17aae"
 typecheck: Consider types containing coercions non-Typeable

 This was previously a panic and caused #13871. I believe just saying
 these types simply aren't Typeable should be correct.

 Test Plan: Validate, check `T13871`

 Reviewers: goldfire, austin

 Subscribers: rwbarton, thomie, RyanGlScott

 GHC Trac Issues: #13871

 Differential Revision: https://phabricator.haskell.org/D3672
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13871#comment:5>
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