[GHC] #13352: Strange requirement for re-exported duplicate record fields

[GHC]

#13352: Strange requirement for re-exported duplicate record fields
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        Reporter:  crockeea          |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.2
      Resolution:                    |             Keywords:  orf
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 adamgundry):

 Sorry, I've only just seen this as ezyang's CC missed. :(

 This is an awkward corner of the `DuplicateRecordFields` implementation:
 as you've observed, the extension needs to be enabled at the definition
 site of (all but one of) a set of record fields in order for them to be
 re-exported by a single module. In principle it would be possible to fix
 this by changing the implementation to mangle selector names regardless of
 whether the extension is enabled. However, I suspect this would be a
 nontrivial amount of work relative to the benefit.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13352#comment:3>
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