[GHC] #15300: Unboxed Sums Crash

[GHC]

#15300: Unboxed Sums Crash
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        Reporter:  andrewthad        |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.5
      Resolution:                    |             Keywords:  UnboxedSums
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by andrewthad):

 For a smaller reproducer, I've reused https://github.com/andrewthad
 /corrupted-memory-example. On master, I've basically got a copy of
 `packed` with everything stripped out that isn't needed to demonstrate
 this particular problem. I'm going to try to golf it down a little more
 today.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15300#comment:9>
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