[GHC] #7145: Incorrect redundant import warning

[GHC]

#7145: Incorrect redundant import warning
---------------------------------+------------------------------------------
    Reporter:  edsko             |       Owner:                  
        Type:  bug               |      Status:  patch           
    Priority:  normal            |   Milestone:  7.8.1           
   Component:  Compiler          |     Version:  7.4.2           
    Keywords:                    |          Os:  Unknown/Multiple
Architecture:  Unknown/Multiple  |     Failure:  None/Unknown    
  Difficulty:  Unknown           |    Testcase:                  
   Blockedby:                    |    Blocking:                  
     Related:                    |  
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Changes (by pcapriotti):

  * status:  new => patch
  * difficulty:  => Unknown
  * milestone:  => 7.8.1


Comment:

 The problem is that constructors/methods exported as children of a type or
 class are not currently considered used.

 Attached is a patch that fixes that in the case of unqualified exported
 entities. For qualified entities, the subordinate names can shadow other
 reader names (as the test case `T7145b` shows), so we don't add it.

 Since the import has to be qualified, anyway, in that case, this should
 not matter.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7145#comment:1>
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