Hi Mauro, FYI, the error/warning still remains. tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: 6a98c9cae232800c319ed69e1063480d31430887 commit: dc7bbea90075b57772e9a28043061bf71d96f06f media: platform: rename marvell-ccic/ to marvell/ date: 12 months ago config: s390-buildonly-randconfig-r003-20230308 (https://download.01.org/0day-ci/archive/20230309/202303090557.mLLxrNKE-lkp@xxxxxxxxx/config) compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project 67409911353323ca5edf2049ef0df54132fa1ca7) 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 s390 cross compiling tool for clang build # apt-get install binutils-s390x-linux-gnu # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=dc7bbea90075b57772e9a28043061bf71d96f06f git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git git fetch --no-tags linus master git checkout dc7bbea90075b57772e9a28043061bf71d96f06f # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=s390 olddefconfig COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=s390 SHELL=/bin/bash drivers/media/platform/ 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/202303090557.mLLxrNKE-lkp@xxxxxxxxx/ All warnings (new ones prefixed by >>): In file included from drivers/media/platform/marvell/mmp-driver.c:17: In file included from include/media/v4l2-device.h:13: In file included from include/media/v4l2-subdev.h:15: In file included from include/media/v4l2-common.h:270: In file included from include/linux/spi/spi.h:15: In file included from include/linux/scatterlist.h:9: In file included from arch/s390/include/asm/io.h:75: include/asm-generic/io.h:464:31: 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:477:61: 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/big_endian.h:37:59: note: expanded from macro '__le16_to_cpu' #define __le16_to_cpu(x) __swab16((__force __u16)(__le16)(x)) ^ include/uapi/linux/swab.h:102:54: note: expanded from macro '__swab16' #define __swab16(x) (__u16)__builtin_bswap16((__u16)(x)) ^ In file included from drivers/media/platform/marvell/mmp-driver.c:17: In file included from include/media/v4l2-device.h:13: In file included from include/media/v4l2-subdev.h:15: In file included from include/media/v4l2-common.h:270: In file included from include/linux/spi/spi.h:15: In file included from include/linux/scatterlist.h:9: In file included from arch/s390/include/asm/io.h:75: include/asm-generic/io.h:490:61: 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/big_endian.h:35:59: note: expanded from macro '__le32_to_cpu' #define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x)) ^ include/uapi/linux/swab.h:115:54: note: expanded from macro '__swab32' #define __swab32(x) (__u32)__builtin_bswap32((__u32)(x)) ^ In file included from drivers/media/platform/marvell/mmp-driver.c:17: In file included from include/media/v4l2-device.h:13: In file included from include/media/v4l2-subdev.h:15: In file included from include/media/v4l2-common.h:270: In file included from include/linux/spi/spi.h:15: In file included from include/linux/scatterlist.h:9: In file included from arch/s390/include/asm/io.h:75: include/asm-generic/io.h:501:33: 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:511:59: 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:521:59: 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); ~~~~~~~~~~ ^ include/asm-generic/io.h:609:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] readsb(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ include/asm-generic/io.h:617:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] readsw(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ include/asm-generic/io.h:625:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] readsl(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ include/asm-generic/io.h:634:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] writesb(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ include/asm-generic/io.h:643:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] writesw(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ include/asm-generic/io.h:652:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] writesl(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ >> drivers/media/platform/marvell/mmp-driver.c:364:34: warning: unused variable 'mmpcam_of_match' [-Wunused-const-variable] static const struct of_device_id mmpcam_of_match[] = { ^ 13 warnings generated. vim +/mmpcam_of_match +364 drivers/media/platform/marvell/mmp-driver.c bb0a896e3d5083 drivers/media/video/marvell-ccic/mmp-driver.c Jonathan Corbet 2011-12-30 363 83c40e6611ec1e drivers/media/platform/marvell-ccic/mmp-driver.c Lubomir Rintel 2019-05-28 @364 static const struct of_device_id mmpcam_of_match[] = { 83c40e6611ec1e drivers/media/platform/marvell-ccic/mmp-driver.c Lubomir Rintel 2019-05-28 365 { .compatible = "marvell,mmp2-ccic", }, 83c40e6611ec1e drivers/media/platform/marvell-ccic/mmp-driver.c Lubomir Rintel 2019-05-28 366 {}, 83c40e6611ec1e drivers/media/platform/marvell-ccic/mmp-driver.c Lubomir Rintel 2019-05-28 367 }; 08aac0e32fe44b drivers/media/platform/marvell-ccic/mmp-driver.c Lubomir Rintel 2019-07-22 368 MODULE_DEVICE_TABLE(of, mmpcam_of_match); 67a8dbbc4e04cd drivers/media/video/marvell-ccic/mmp-driver.c Jonathan Corbet 2011-06-11 369 :::::: The code at line 364 was first introduced by commit :::::: 83c40e6611ec1e548ece34f6940f516333abc16a media: marvell-ccic/mmp: add devicetree support :::::: TO: Lubomir Rintel <lkundrak@xxxxx> :::::: CC: Mauro Carvalho Chehab <mchehab+samsung@xxxxxxxxxx> -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests