Incorrect "unnecessary import" warning

With the code:

{-# OPTIONS_GHC -Wall -fno-warn-missing-methods #-}
module Test where
import Data.Typeable
import Data.Data
data Test = Test
instance Typeable Test where

I get the warning:

    Warning: Module `Data.Typeable' is imported, but nothing from it is used
               except perhaps instances visible in `Data.Typeable'
             To suppress this warning, use: import Data.Typeable()

It seems like it's decided to pick up Typeable from Data.Data, but it's also available from Data.Typeable which would be a better choice. I'm not sure how this should be solved, but the current behaviour seems incorrect. Perhaps if two modules are imported, both of which export the same thing, they should both be allowed.

Trac metadata

Trac field	Value
Version	6.10.4
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
CC	ndmitchell@gmail.com
Operating system
Architecture