[GHC] #13704: -main-is flag should change exports in default module header

[GHC]

#13704: -main-is flag should change exports in default module header
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        Reporter:  cdsmith           |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.1
      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):

 This sounds like a perfectly reasonable behavior to me. The patch also
 looks reasonable, although it should reference this ticket. Also a test
 would be nice. We might also want to mention this departure from the
 Report in `docs/users-guide/infelicities.rst` (although perhaps not given
 that `-main-is` is something of a GHC-specific feature).

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13704#comment:3>
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