[GHC] #11066: Inacessible branch should be warning - otherwise breaks type soundness?

[GHC]

#11066: Inacessible branch should be warning - otherwise breaks type soundness?
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        Reporter:  rrnewton          |                Owner:  (none)
            Type:  bug               |               Status:  closed
        Priority:  high              |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  7.10.2
      Resolution:  fixed             |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Incorrect         |  Unknown/Multiple
  warning at compile-time            |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #8128, #8740      |  Differential Rev(s):  Phab:D1454,
       Wiki Page:                    |  Phab:D4744
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Comment (by Ryan Scott <ryan.gl.scott@…>):

 In [changeset:"90e99c4cfd601601e56fc6041186ca3e070408d9/ghc"
 90e99c4c/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="90e99c4cfd601601e56fc6041186ca3e070408d9"
 Add tests for #8128 and #8740

 Commit 08073e16cf672d8009309e4e55d4566af1ecaff4 (#11066) ended up
 fixing these, fortunately enough.
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11066#comment:50>
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