[GHC] #11103: DuplicateRecordFields + TemplateHaskell

[GHC]

#11103: DuplicateRecordFields + TemplateHaskell
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        Reporter:  adamgundry        |                Owner:  adamgundry
            Type:  bug               |               Status:  patch
        Priority:  normal            |            Milestone:  8.0.1
       Component:  Template Haskell  |              Version:  7.11
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D1586
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"4b161c93dba774cc8051cf40a2024ad86f3259f2/ghc"
 4b161c93/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="4b161c93dba774cc8051cf40a2024ad86f3259f2"
 Reify DuplicateRecordFields by label, rather than by selector

 See `Note [Reifying field labels]` in `TcSplice`. This makes
 typical uses of TH work better with `DuplicateRecordFields`.
 If `reify` is called on the `Name` of a field label produced by
 the output of a previous `reify`, and there are multiple  fields
 with that label defined in the same module, it may fail with
 an ambiguity error.

 Test Plan:
 Added tests, and manually tested that this makes
 Aeson's `deriveJSON` avoid the `$sel:` prefixes.

 Reviewers: simonpj, goldfire, austin, bgamari

 Reviewed By: bgamari

 Subscribers: thomie

 Differential Revision: https://phabricator.haskell.org/D1586

 GHC Trac Issues: #11103
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11103#comment:3>
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