reproduce (this is a W=1 build):
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # https://github.com/zen-kernel/zen-kernel/commit/8964d2061c8f25fc8c96de75a0f9e3234ae61c6e
        git remote add zen https://github.com/zen-kernel/zen-kernel
        git fetch --no-tags zen 6.9/prjc
        git checkout 8964d2061c8f25fc8c96de75a0f9e3234ae61c6e
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-14.1.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=mips olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-14.1.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=mips SHELL=/bin/bash