[GHC] #14715: GHC 8.4.1-alpha regression with PartialTypeSignatures

[GHC]

#14715: GHC 8.4.1-alpha regression with PartialTypeSignatures
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        Reporter:  RyanGlScott       |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  highest           |            Milestone:  8.4.1
       Component:  Compiler (Type    |              Version:  8.4.1-alpha1
  checker)                           |             Keywords:
      Resolution:                    |  PartialTypeSignatures
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  GHC rejects       |  Unknown/Multiple
  valid program                      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Simon Peyton Jones <simonpj@…>):

 In [changeset:"e7c3878dacbad8120aacbe4423857b5ca9b43eb4/ghc"
 e7c3878d/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="e7c3878dacbad8120aacbe4423857b5ca9b43eb4"
 Move zonkWC to the right place in simplfyInfer

 runTcSWithEvBinds does some unification, so the zonkWC
 must be after, not before!  Yikes.  An outright bug.

 This fixes Trac #14715.
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14715#comment:3>
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