[GHC] #12777: reify yields the wrong type in the presence of functional dependencies

[GHC]

#12777: reify yields the wrong type in the presence of functional dependencies
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        Reporter:                    |                Owner:
  facundo.dominguez                  |
            Type:  bug               |               Status:  patch
        Priority:  high              |            Milestone:  8.0.2
       Component:  Template Haskell  |              Version:  8.0.1
      Resolution:                    |             Keywords:  template-
                                     |  haskell reify
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D2659
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"231a3ae1644403c1f295e993105c4346d0db22db/ghc"
 231a3ae1/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="231a3ae1644403c1f295e993105c4346d0db22db"
 Have reify work for local variables with functional dependencies.

 It turned out that finalizers were run too early and information
 resulting from simplifying constraints was not available.

 This patch runs finalizers after a first call to simplifyTop, and
 then calls simplifyTop a second time to deal with constraints
 that could result from running the finalizers.

 Fixes T12777

 Test Plan: ./validate

 Reviewers: goldfire, simonpj, bgamari, austin

 Reviewed By: simonpj

 Subscribers: mpickering, mboes, thomie

 Differential Revision: https://phabricator.haskell.org/D2659

 GHC Trac Issues: #12777
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12777#comment:9>
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