reproduce (this is a W=1 build):
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # install powerpc cross compiling tool for clang build
        # apt-get install binutils-powerpc64-linux-gnu
        # https://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio.git/commit/?id=0dd7ce9e2be9a81dc04549e8e604931c19547531
        git remote add linusw-gpio https://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio.git
        git fetch --no-tags linusw-gpio b4/descriptors-wireless
        git checkout 0dd7ce9e2be9a81dc04549e8e604931c19547531
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-19 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=powerpc olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-19 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=powerpc SHELL=/bin/bash drivers/net/wireless/ath/ath9k/