tell moveFile to overwrite existing files

Utility/PosixFiles.hs

@@ -19,12 +19,15 @@ import System.PosixCompat.Files as X hiding (rename)
 #ifndef mingw32_HOST_OS
 import System.Posix.Files (rename)
 #else
-import System.Win32.File (moveFile)
+import qualified System.Win32.File as Win32
 #endif
 
 {- System.PosixCompat.Files.rename on Windows calls renameFile,
- - so cannot rename directories. Instead, use Win32 moveFile, which can. -}
+ - so cannot rename directories. 
+ -
+ - Instead, use Win32 moveFile, which can. It needs to be told to overwrite
+ - any existing file. -}
 #ifdef mingw32_HOST_OS
 rename :: FilePath -> FilePath -> IO ()
-rename = moveFile
+rename src dest = Win32.moveFileEx src dest Win32.mOVEFILE_REPLACE_EXISTING
 #endif