[GHC] #1148: Bad warnings about unused imports that are in fact needed

[GHC]

#1148: Bad warnings about unused imports that are in fact needed
-----------------------------------+----------------------------------------
 Reporter:  brianh                 |          Owner:         
     Type:  bug                    |         Status:  new    
 Priority:  lowest                 |      Milestone:  _|_    
Component:  Compiler               |        Version:  6.8.2  
 Severity:  trivial                |     Resolution:         
 Keywords:  warning unused import  |     Difficulty:  Unknown
 Testcase:                         |   Architecture:  x86    
       Os:  Windows                |  
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Changes (by Eelis-):

  * version:  6.6 => 6.8.2

Comment:

 I ran into this bug, and isolated it to this:

 {{{
 import List
 import Prelude
 main = return () where b = List.null ""
 }}}

 GHC warns that nothing from List is used, but the code fails to compile
 without the import.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/1148#comment:4>
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