Ticket #5112 (closed bug: invalid)
Incorrect warnings about unqualified imports being redundant
Mixing qualified and unqualified imports can confuse the compiler.
Create the file BadWarning?.hs.
module BadWarning where import Data.Map import qualified Data.Map as M example = empty
Run ghci -W BadWarning.hs, and you get:
BadWarning.hs:4:1: Warning: The import of `Data.Map' is redundant except perhaps to import instances from `Data.Map' To import instances alone, use: import Data.Map() Ok, modules loaded: BadWarning.
This looks similar to #3992, but that bug does not repro for me, so I think the issue is slightly different.