[GHC] #14282: tagToEnum# . dataToTag# not optimized away

[GHC]

#14282: tagToEnum# . dataToTag# not optimized away
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        Reporter:  dfeuer            |                Owner:  dfeuer
            Type:  bug               |               Status:  patch
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.2.1
      Resolution:                    |             Keywords:  datacon-tags
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D4375
       Wiki Page:                    |
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Changes (by dfeuer):

 * status:  new => patch
 * differential:   => Phab:D4375


Comment:

 I've put up a differential adding the necessary explanation.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14282#comment:8>
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