[GHC] #11715: There's something fishy going on with Constraint

[GHC]

#11715: There's something fishy going on with Constraint
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        Reporter:  bgamari           |                Owner:
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:  8.0.1
       Component:  Compiler (Type    |              Version:  8.0.1-rc1
  checker)                           |
      Resolution:                    |             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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Comment (by bgamari):

 So I believe that the culprit lies somewhere in the simplifier since the
 `dump-ds` output looks reasonable but `dump-simpl` reveals that the
 `Typeable Proxy` dictionary has been floated to the top level and has been
 applied to either `*` or `Constraint`, depending upon the order of the
 `print` statements, and that the same dictionary is used in both `print`s.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11715#comment:2>
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