reproduce (this is a W=1 build):
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # https://git.kernel.org/pub/scm/linux/kernel/git/broonie/ci.git/commit/?id=dd0b6b1f29b92202d03a6d2dd7d65ecead27941a
        git remote add broonie-ci https://git.kernel.org/pub/scm/linux/kernel/git/broonie/ci.git
        git fetch --no-tags broonie-ci filecmeuqH
        git checkout dd0b6b1f29b92202d03a6d2dd7d65ecead27941a
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-20 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=hexagon olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-20 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=hexagon SHELL=/bin/bash drivers/firmware/cirrus/test/