Hi, kernel test robot noticed the following build warnings: [auto build test WARNING on groeck-staging/hwmon-next] [also build test WARNING on robh/for-next linus/master v6.3-rc7] [cannot apply to brgl/gpio/for-next next-20230418] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/nick-hawkins-hpe-com/gpio-gxp-Add-HPE-GXP-GPIO/20230418-233513 base: https://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging.git hwmon-next patch link: https://lore.kernel.org/r/20230418152824.110823-3-nick.hawkins%40hpe.com patch subject: [PATCH v1 2/9] hwmon: (gxp_fan_ctrl) Give GPIO access to fan data config: hexagon-randconfig-r045-20230419 (https://download.01.org/0day-ci/archive/20230419/202304192243.9hwJ1Cad-lkp@xxxxxxxxx/config) compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project 437b7602e4a998220871de78afcb020b9c14a661) 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 # https://github.com/intel-lab-lkp/linux/commit/be3722d7f32fea1ea375090d05cbfdd3dd4e04d3 git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review nick-hawkins-hpe-com/gpio-gxp-Add-HPE-GXP-GPIO/20230418-233513 git checkout be3722d7f32fea1ea375090d05cbfdd3dd4e04d3 # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=hexagon olddefconfig COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=hexagon SHELL=/bin/bash block/partitions/ drivers/hwmon/ If you fix the issue, kindly add following tag where applicable | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Link: https://lore.kernel.org/oe-kbuild-all/202304192243.9hwJ1Cad-lkp@xxxxxxxxx/ All warnings (new ones prefixed by >>): In file included from drivers/hwmon/gxp-fan-ctrl.c:7: In file included from include/linux/io.h:13: In file included from arch/hexagon/include/asm/io.h:334: include/asm-generic/io.h:547:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] val = __raw_readb(PCI_IOBASE + addr); ~~~~~~~~~~ ^ include/asm-generic/io.h:560:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr)); ~~~~~~~~~~ ^ include/uapi/linux/byteorder/little_endian.h:37:51: note: expanded from macro '__le16_to_cpu' #define __le16_to_cpu(x) ((__force __u16)(__le16)(x)) ^ In file included from drivers/hwmon/gxp-fan-ctrl.c:7: In file included from include/linux/io.h:13: In file included from arch/hexagon/include/asm/io.h:334: include/asm-generic/io.h:573:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr)); ~~~~~~~~~~ ^ include/uapi/linux/byteorder/little_endian.h:35:51: note: expanded from macro '__le32_to_cpu' #define __le32_to_cpu(x) ((__force __u32)(__le32)(x)) ^ In file included from drivers/hwmon/gxp-fan-ctrl.c:7: In file included from include/linux/io.h:13: In file included from arch/hexagon/include/asm/io.h:334: include/asm-generic/io.h:584:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] __raw_writeb(value, PCI_IOBASE + addr); ~~~~~~~~~~ ^ include/asm-generic/io.h:594:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr); ~~~~~~~~~~ ^ include/asm-generic/io.h:604:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr); ~~~~~~~~~~ ^ >> drivers/hwmon/gxp-fan-ctrl.c:32:4: warning: no previous prototype for function 'get_fans_installed' [-Wmissing-prototypes] u8 get_fans_installed(void) ^ drivers/hwmon/gxp-fan-ctrl.c:32:1: note: declare 'static' if the function is not intended to be used outside of this translation unit u8 get_fans_installed(void) ^ static >> drivers/hwmon/gxp-fan-ctrl.c:52:4: warning: no previous prototype for function 'get_fans_failed' [-Wmissing-prototypes] u8 get_fans_failed(void) ^ drivers/hwmon/gxp-fan-ctrl.c:52:1: note: declare 'static' if the function is not intended to be used outside of this translation unit u8 get_fans_failed(void) ^ static 8 warnings generated. vim +/get_fans_installed +32 drivers/hwmon/gxp-fan-ctrl.c 31 > 32 u8 get_fans_installed(void) 33 { 34 static u8 val; 35 36 val = readb(drvdata->plreg + OFS_FAN_INST); 37 38 return val; 39 } 40 EXPORT_SYMBOL(get_fans_installed); 41 42 static long fan_failed(struct device *dev, int fan) 43 { 44 struct gxp_fan_ctrl_drvdata *drvdata = dev_get_drvdata(dev); 45 u8 val; 46 47 val = readb(drvdata->plreg + OFS_FAN_FAIL); 48 49 return !!(val & BIT(fan)); 50 } 51 > 52 u8 get_fans_failed(void) 53 { 54 static u8 val; 55 56 val = readb(drvdata->plreg + OFS_FAN_FAIL); 57 58 return val; 59 } 60 EXPORT_SYMBOL(get_fans_failed); 61 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests