reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/cel/linux.git/commit/?id=bf18662aa8520b408479ac0e99d8168b5ac18106
        git remote add cel https://git.kernel.org/pub/scm/linux/kernel/git/cel/linux
        git fetch --no-tags cel nfsd-testing
        git checkout bf18662aa8520b408479ac0e99d8168b5ac18106

        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=$HOME/0day COMPILER=gcc-15.2.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=parisc olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-15.2.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=parisc SHELL=/bin/bash