[GHC] #2467: orphan instance warnings are badly behaved

[GHC]

#2467: orphan instance warnings are badly behaved
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    Reporter:  duncan            |        Owner:                  
        Type:  bug               |       Status:  new             
    Priority:  normal            |    Milestone:  6.12 branch     
   Component:  Compiler          |      Version:  6.8.2           
    Severity:  normal            |   Resolution:                  
    Keywords:                    |   Difficulty:  Unknown         
    Testcase:                    |           Os:  Unknown/Multiple
Architecture:  Unknown/Multiple  |  
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Comment (by igloo):

 Replying to [comment:8 simonpj]:
 > Indeed, your code is legitimate, and that's why warnings are just
 warnings!
 >
 > More concretely, what would you like?  A special kind of warning that
 (uniquely) does not make -Werror abort the compilation?  That seems a bit
 irregular...  But perhaps you have something in mind.

 Perhaps we should have separate control for two different classes of
 orphan warnings:
  * those where the class and all the types are in other packages (and thus
 you may not be able to easily avoid the instance, e.g. if everything is in
 the base package).
  * the rest

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/2467#comment:11>
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