reproduce (this is a W=1 build): git clone https://github.com/intel/lkp-tests.git ~/lkp-tests # install riscv cross compiling tool for clang build # apt-get install binutils-riscv64-linux-gnu git checkout linus/master b4 shazam https://lore.kernel.org/r/20240614040133.24967-2-jason-jh.lin@mediatek.com # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-19 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=riscv olddefconfig COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-19 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=riscv SHELL=/bin/bash drivers/mailbox/