[GHC] #15067: When Typeable and unboxed sums collide, GHC panics

[GHC]

#15067: When Typeable and unboxed sums collide, GHC panics
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        Reporter:  RyanGlScott       |                Owner:  (none)
            Type:  bug               |               Status:  patch
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler (Type    |              Version:  8.4.1
  checker)                           |             Keywords:  Typeable,
      Resolution:                    |  UnboxedSums
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  crash or panic                     |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #13276            |  Differential Rev(s):  Phab:D4622,
       Wiki Page:                    |  Phab:D4623
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"f0212a93a2f3d4fb564c1025cca0dfd3050487e4/ghc"
 f0212a93/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="f0212a93a2f3d4fb564c1025cca0dfd3050487e4"
 TcInteract: Ensure that tycons have representations before solving for
 Typeable

 Summary: This fixes #15067.

 Test Plan: Validate

 Subscribers: thomie, carter, RyanGlScott

 GHC Trac Issues: #15067

 Differential Revision: https://phabricator.haskell.org/D4623
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15067#comment:5>
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