reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-nomadik.git/commit/?id=bd19dc64243c585c8cb3c164b77a3f5d42b92771
        git remote add linusw-nomadik https://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-nomadik.git
        git fetch --no-tags linusw-nomadik b4/ux500-audio-graph-card2
        git checkout bd19dc64243c585c8cb3c164b77a3f5d42b92771

        # install sparc64 cross compiling tool for clang build
        # apt-get install binutils-sparc64-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=$HOME/0day COMPILER=clang-22 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=sparc64 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-22 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=sparc64 SHELL=/bin/bash