reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging.git/commit/?id=068e2e1754d7c9e92e07c8332b2b64673b4989cc
        git remote add groeck-staging https://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging.git
        git fetch --no-tags groeck-staging testing
        git checkout 068e2e1754d7c9e92e07c8332b2b64673b4989cc
        # 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 lib/