[GHC] #15599: typeclass inference depends on whether a module is exposed.

[GHC]

#15599: typeclass inference depends on whether a module is exposed.
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        Reporter:  gleachkr          |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.2.3
       Component:  Compiler          |              Version:  8.2.2
      Resolution:                    |             Keywords:
Operating System:  Linux             |         Architecture:
 Type of failure:  Incorrect result  |  Unknown/Multiple
  at runtime                         |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by AndreasK):

 For another data point:

 On windows:
 {{{
 $ bash test.sh
 Building project...
 These two results should be the same, since the only difference between
 the files is that one is an exported module
 *Tests.Good> Flag {checkFlag = True}
 *Tests.Bad> Flag {checkFlag = False}
 Here it is again with 8.4.3:
 Building project...
 *Tests.Bad> Flag {checkFlag = True}
 *Tests.Good> Flag {checkFlag = True}
 }}}

 The ghci script is hardcoded to linux paths so didn't work on windows.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15599#comment:7>
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