reproduce (this is a W=1 build):
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # https://github.com/avpatel/linux/commit/bbd0c6fe3c7a582057ffa9bb1366c7f699dcd006
        git remote add avpatel https://github.com/avpatel/linux.git
        git fetch --no-tags avpatel riscv_raid6_rvv_v5
        git checkout bbd0c6fe3c7a582057ffa9bb1366c7f699dcd006
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-20 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=i386 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-20 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash drivers/acpi/apei/