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

[GHC]

#15067: When Typeable and unboxed sums collide, GHC panics
-------------------------------------+-------------------------------------
        Reporter:  RyanGlScott       |                Owner:  (none)
            Type:  bug               |               Status:  new
        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):
       Wiki Page:                    |
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Changes (by RyanGlScott):

 * related:   => #13276


Comment:

 Ah, #13276 claims that unboxed sums shouldn't be `Typeable` at all. I'm
 fine with this, but it would be nice to have a proper error message in the
 event one tries to do this instead of panicking. (The commit which
 established this limitation, 42ff5d97b486d50b0d10e474f47e86822bb71ace,
 didn't add any regression tests, which might explain why these
 infelicities went unnoticed.)

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15067#comment:2>
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