reproduce (this is a W=1 build):
        # https://github.com/morimoto/linux/commit/89bf1d2520ff02f48039d27411baf6b923f0b16d
        git remote add morimoto https://github.com/morimoto/linux
        git fetch --no-tags morimoto sound-cleanup-2026-04-06
        git checkout 89bf1d2520ff02f48039d27411baf6b923f0b16d

        # install powerpc cross compiling tool for clang build
        # apt-get install binutils-powerpc-linux-gnu
        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=$HOME/0day COMPILER=clang-20 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=powerpc olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-20 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=powerpc SHELL=/bin/bash sound/soc/