[GHC] #13750: GHC produces incorrect coercions in hairy code

[GHC]

#13750: GHC produces incorrect coercions in hairy code
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        Reporter:  dfeuer            |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  highest           |            Milestone:  8.2.2
       Component:  Compiler          |              Version:  8.2.1-rc2
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  Runtime crash     |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #13429            |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Simon Peyton Jones <simonpj@…>):

 In [changeset:"ef07010cf4f480d9f595a71cf5b009884522a75e/ghc"
 ef07010c/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="ef07010cf4f480d9f595a71cf5b009884522a75e"
 Test Trac #13750
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13750#comment:12>
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