[commit: ghc] master: Fix potential `mingw32_HOST_OS` -Werror failure (83c5821)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/83c5821f851f7c7084eb8b7b6fa482915915a503/ghc

>---------------------------------------------------------------

commit 83c5821f851f7c7084eb8b7b6fa482915915a503
Author: Herbert Valerio Riedel <hvr at gnu.org>
Date:   Sat Sep 20 19:11:48 2014 +0200

    Fix potential `mingw32_HOST_OS` -Werror failure


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83c5821f851f7c7084eb8b7b6fa482915915a503
 libraries/base/GHC/Conc/Windows.hs | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/libraries/base/GHC/Conc/Windows.hs b/libraries/base/GHC/Conc/Windows.hs
index c01281a..aef7fbf 100644
--- a/libraries/base/GHC/Conc/Windows.hs
+++ b/libraries/base/GHC/Conc/Windows.hs
@@ -38,9 +38,8 @@ module GHC.Conc.Windows
        , toWin32ConsoleEvent
        ) where
 
-import Control.Monad
+import Control.Monad (unless)
 import Data.Bits (shiftR)
-import Data.Maybe (Maybe(..))
 import Data.Typeable
 import GHC.Base
 import GHC.Conc.Sync