tree: https://github.com/frank-w/BPI-R2-4.14 5.8-main head: c005c8640ef47f9bc527cd2d669f887ce1018989 commit: f2f6eae7483a73ffcc8fc71c1dce29ea227a4cef [6/62] mt6625l: add changes outside driver dir config: arm64-randconfig-r035-20200812 (attached as .config) compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 30c1633386e7cfb01c0a54b31ccf4c3a3873e71b) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # install arm64 cross compiling tool for clang build # apt-get install binutils-aarch64-linux-gnu git checkout f2f6eae7483a73ffcc8fc71c1dce29ea227a4cef # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): struct regmap *pwrap_node_to_regmap(struct device_node *np) ^ drivers/soc/mediatek/mtk-pmic-wrap.c:2022:1: note: declare 'static' if the function is not intended to be used outside of this translation unit struct regmap *pwrap_node_to_regmap(struct device_node *np) ^ static 1 warning generated. vim +/pwrap_node_to_regmap +2022 drivers/soc/mediatek/mtk-pmic-wrap.c 2021 2023 { 2024 struct platform_device *pdev; 2025 struct pmic_wrapper *wrp; 2026 pdev = of_find_device_by_node(np); 2027 if (!pdev) 2028 return ERR_PTR(-ENODEV); 2029 wrp = platform_get_drvdata(pdev); 2030 return wrp->regmap; 2031 } 2032 EXPORT_SYMBOL_GPL(pwrap_node_to_regmap); 2033 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org