[GHC] #12702: Don't warn about redundant constraints for necessary

[GHC]

#12702: Don't warn about redundant constraints for necessary
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        Reporter:  crockeea          |                Owner:
            Type:  bug               |               Status:  closed
        Priority:  normal            |            Milestone:  8.0.2
       Component:  Compiler          |              Version:  8.0.1
      Resolution:  fixed             |             Keywords:
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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Changes (by RyanGlScott):

 * status:  new => closed
 * resolution:   => fixed
 * milestone:   => 8.0.2


Comment:

 I can't reproduce the warning on GHC 8.0.2.

 Sadly, this test case requires lots of `singletons` machinery, which is
 darn-near impossible to boil down to a simple test case. I'm going to just
 close this as being fixed in 8.0.2.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12702#comment:3>
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