reproduce (this is a W=1 build):
git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
# https://git.kernel.org/pub/scm/linux/kernel/git/clk/linux.git/commit/?id=9f8bbc66021282d0646d1f8422265c72e671b5d1
git remote add clk https://git.kernel.org/pub/scm/linux/kernel/git/clk/linux.git
git fetch --no-tags clk clk-kunit
git checkout 9f8bbc66021282d0646d1f8422265c72e671b5d1
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-18 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=i386 olddefconfig
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-18 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash