reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/lee/leds.git/commit/?id=14ef0738a31dcecfbba38626884b7d9a60b75cd0
        git remote add lee-leds https://git.kernel.org/pub/scm/linux/kernel/git/lee/leds.git
        git fetch --no-tags lee-leds for-leds-next
        git checkout 14ef0738a31dcecfbba38626884b7d9a60b75cd0
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=i386 olddefconfig
        make W=1 O=build_dir ARCH=i386 SHELL=/bin/bash drivers/leds/