reproduce (this is a W=1 build):
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # install arm cross compiling tool for clang build
        # apt-get install binutils-arm-linux-gnueabi
        git remote add drm-exynos https://git.kernel.org/pub/scm/linux/kernel/git/daeinki/drm-exynos.git
        git fetch drm-exynos exynos-drm-next
        git checkout drm-exynos/exynos-drm-next
        b4 shazam https://lore.kernel.org/r/20240526202115.129049-3-sui.jingfeng@linux.dev
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-14 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=arm olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-14 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=arm SHELL=/bin/bash drivers/gpu/drm/omapdrm/