reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/cel/linux.git/commit/?id=2b5b97ec0f7a484e81bedf71e223f38b0feb98ca
        git remote add cel https://git.kernel.org/pub/scm/linux/kernel/git/cel/linux
        git fetch --no-tags cel nfsv3-xdrgen
        git checkout 2b5b97ec0f7a484e81bedf71e223f38b0feb98ca

        # install arm cross compiling tool for clang build
        # apt-get install binutils-arm-linux-gnueabi
        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=$HOME/0day COMPILER=clang-17 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=arm olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-17 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=arm SHELL=/bin/bash fs/nfsd/