reproduce (this is a W=1 build): # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=5ab154f1463a111e1dc8fd5d31eaa7a2a71fe2e6 git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git git fetch --no-tags linus master git checkout 5ab154f1463a111e1dc8fd5d31eaa7a2a71fe2e6 # apt-get install sparse # sparse version: v0.6.4-71-g610d841d # save the config file mkdir build_dir && cp config build_dir/.config make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__ -fmax-errors=unlimited -fmax-warnings=unlimited' O=build_dir ARCH=um olddefconfig make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__ -fmax-errors=unlimited -fmax-warnings=unlimited' O=build_dir ARCH=um SHELL=/bin/bash drivers/vdpa/vdpa_user/ io_uring/ kernel/bpf/