reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git/commit/?id=065c245ab6ac3537488e5c410d38d4768824dd07
        git remote add arnd-playground https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git
        git fetch --no-tags arnd-playground randconfig-7.3-next
        git checkout 065c245ab6ac3537488e5c410d38d4768824dd07

        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=$HOME/0day COMPILER=gcc-16.1.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=sh olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-16.1.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=sh SHELL=/bin/bash drivers/tty/serial/8250/