reproduce:
        # apt-get install sparse
        # sparse version: v0.6.4-39-gce1a6720-dirty
        # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=1e3cb6c321be2e5295dcaa94c2bf42a43a47a067
        git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
        git fetch --no-tags linus master
        git checkout 1e3cb6c321be2e5295dcaa94c2bf42a43a47a067
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=x86_64 olddefconfig
        make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=x86_64 SHELL=/bin/bash ./ arch/x86/events/ arch/x86/hyperv/ arch/x86/kernel/ arch/x86/kvm/ arch/x86/lib/ arch/x86/mm/ drivers/ fs/ init/ kernel/ lib/ mm/ net/9p/ net/core/ net/ipv4/ net/ipv6/ net/sunrpc/ security/ sound/core/ sound/soc/codecs/ sound/soc/generic/ sound/soc/intel/atom/sst/