reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git/commit/?id=bd9bfac7160b3f7ff7cb190bcf2b5c0108bddf5b
        git remote add arnd-playground https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git
        git fetch --no-tags arnd-playground to-build
        git checkout bd9bfac7160b3f7ff7cb190bcf2b5c0108bddf5b
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-15.1.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=parisc olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-15.1.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=parisc prepare