reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/melver/linux.git/commit/?id=55ba795143c3f548c5d0d7ead143ebea3ee8405c
        git remote add melver https://git.kernel.org/pub/scm/linux/kernel/git/melver/linux.git
        git fetch --no-tags melver ctx-analysis/dev
        git checkout 55ba795143c3f548c5d0d7ead143ebea3ee8405c

        # 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/