reproduce (this is a W=1 build):
        # https://github.com/krzk/linux/commit/713ad4dd44fc1f8e72351e3d0217dde04097d54c
        git remote add krzk-github https://github.com/krzk/linux
        git fetch --no-tags krzk-github pending/dt-bindings-qcom-new-and-fixes-for-warnings-linux-next
        git checkout 713ad4dd44fc1f8e72351e3d0217dde04097d54c
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=i386 olddefconfig
        make W=1 O=build_dir ARCH=i386 SHELL=/bin/bash arch/x86/ samples/