reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/chunkuang.hu/linux.git/commit/?id=8db28701a2a05fcdbd8ec6364f0e817ee0aeff26
        git remote add chunkuang-hu https://git.kernel.org/pub/scm/linux/kernel/git/chunkuang.hu/linux.git
        git fetch --no-tags chunkuang-hu mediatek-drm-next
        git checkout 8db28701a2a05fcdbd8ec6364f0e817ee0aeff26

        # clang-22 might not be officially released. Try a lower version if installation fails.
        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=$HOME/0day COMPILER=clang-22 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=hexagon olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-22 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=hexagon SHELL=/bin/bash