reproduce (this is a W=1 build): git clone https://github.com/intel/lkp-tests.git ~/lkp-tests # install um cross compiling tool for clang build # apt-get install binutils-um-linux-gnu # clang-22 might not be officially released. Try a lower version if installation fails. git checkout ec79003c5f9d2c7f9576fc69b8dbda80305cbe3a b4 shazam https://lore.kernel.org/r/20250824083944.523858-10-mbloch@nvidia.com # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-22 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=um olddefconfig COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-22 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=um SHELL=/bin/bash drivers/net/ethernet/mellanox/mlx5/core/