[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 simonpj):

 > The difference that made me try the package-db route was that it seems
 (from a fair amount of experimentation) that you get checkFlag=False when
 the modules from GHC-Repro are not compiled by ghci, but just included,

 What does "just included" mean?  Can you give a sequence of ghc commands
 that demonstrates the problem?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15599#comment:5>
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