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

[GHC]

#13704: -main-is flag should change exports in default module header
-------------------------------------+-------------------------------------
        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:                    |
-------------------------------------+-------------------------------------

Comment (by cdsmith):

 I have a patch for this (https://github.com/google/codeworld/blob/master
 /ghc-artifacts/ghc-8.0.2-default-main.patch) which is easy to port to
 HEAD, but it's not clear to me whether it would be accepted without some
 form of discussion about whether this is the correct behavior.  Any
 thoughts on the matter?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13704#comment:2>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler