The cross i586-mingw32msvc-gcc 4.4.4 from Debian Squeeze does not support
__sync_val_compare_and_swap by default.

Using -march=i686 fixes that and should also result in better code.
Signed-off-by: NStefan Weil <sw@weilnetz.de>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>