reproduce (this is a W=1 build):
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # https://github.com/ambarus/linux-0day/commit/2c7c337e69c51f04f63d04aa2c817eda43cf97ca
        git remote add ambarus https://github.com/ambarus/linux-0day
        git fetch --no-tags ambarus acpm-v3-upstream
        git checkout 2c7c337e69c51f04f63d04aa2c817eda43cf97ca
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-14.2.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=sparc olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-14.2.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=sparc SHELL=/bin/bash