reproduce (this is a W=1 build):
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        git remote add kdave https://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux.git
        git fetch kdave for-next
        git checkout kdave/for-next
        b4 shazam https://lore.kernel.org/r/6ba44b940e4e3eea573cad667ab8c0b2dd8f2c06.1710409033.git.wqu@suse.com
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-13.2.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=m68k olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-13.2.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=m68k SHELL=/bin/bash fs/btrfs/