reproduce (this is a W=1 build):
        git checkout v7.1-rc5
        b4 shazam https://lore.kernel.org/r/19e6858d9db.3a90532342003.5043853571553507480@zohomail.in

        # 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 arch/x86/kernel/ arch/x86/lib/