tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: 1c52283265a462a100ae63ddf58b4e5884acde86 commit: 227d72063fccb2d19b30fb4197fba478514f7d83 dsa: simplify Kconfig symbols and dependencies date: 10 months ago config: s390-randconfig-c005-20220120 (https://download.01.org/0day-ci/archive/20220123/202201230139.E1dqQNmn-lk...) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project f7b7138a62648f4019c55e4671682af1f851f295) 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... git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git git fetch --no-tags linus master git checkout 227d72063fccb2d19b30fb4197fba478514f7d83 # save the config file to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=s390 SHELL=/bin/bash drivers/net/dsa/microchip/ 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 >>): include/uapi/linux/swab.h:19:12: note: expanded from macro '___constant_swab32' (((__u32)(x) & (__u32)0x000000ffUL) << 24) | \ ^ In file included from drivers/net/dsa/microchip/ksz8795_spi.c:14: In file included from include/linux/regmap.h:20: In file included from include/linux/iopoll.h:14: In file included from include/linux/io.h:13: In file included from arch/s390/include/asm/io.h:80: 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:34:59: note: expanded from macro '__le32_to_cpu' #define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x)) ^ include/uapi/linux/swab.h:119:21: note: expanded from macro '__swab32' ___constant_swab32(x) : \ ^ include/uapi/linux/swab.h:20:12: note: expanded from macro '___constant_swab32' (((__u32)(x) & (__u32)0x0000ff00UL) << 8) | \ ^ In file included from drivers/net/dsa/microchip/ksz8795_spi.c:14: In file included from include/linux/regmap.h:20: In file included from include/linux/iopoll.h:14: In file included from include/linux/io.h:13: In file included from arch/s390/include/asm/io.h:80: 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:34:59: note: expanded from macro '__le32_to_cpu' #define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x)) ^ include/uapi/linux/swab.h:119:21: note: expanded from macro '__swab32' ___constant_swab32(x) : \ ^ include/uapi/linux/swab.h:21:12: note: expanded from macro '___constant_swab32' (((__u32)(x) & (__u32)0x00ff0000UL) >> 8) | \ ^ In file included from drivers/net/dsa/microchip/ksz8795_spi.c:14: In file included from include/linux/regmap.h:20: In file included from include/linux/iopoll.h:14: In file included from include/linux/io.h:13: In file included from arch/s390/include/asm/io.h:80: 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:34:59: note: expanded from macro '__le32_to_cpu' #define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x)) ^ include/uapi/linux/swab.h:119:21: note: expanded from macro '__swab32' ___constant_swab32(x) : \ ^ include/uapi/linux/swab.h:22:12: note: expanded from macro '___constant_swab32' (((__u32)(x) & (__u32)0xff000000UL) >> 24))) ^ In file included from drivers/net/dsa/microchip/ksz8795_spi.c:14: In file included from include/linux/regmap.h:20: In file included from include/linux/iopoll.h:14: In file included from include/linux/io.h:13: In file included from arch/s390/include/asm/io.h:80: 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:34:59: note: expanded from macro '__le32_to_cpu' #define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x)) ^ include/uapi/linux/swab.h:120:12: note: expanded from macro '__swab32' __fswab32(x)) ^ In file included from drivers/net/dsa/microchip/ksz8795_spi.c:14: In file included from include/linux/regmap.h:20: In file included from include/linux/iopoll.h:14: In file included from include/linux/io.h:13: In file included from arch/s390/include/asm/io.h:80: 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); ~~~~~~~~~~ ^ static const struct of_device_id ksz8795_dt_ids[] = { ^ 21 warnings generated. vim +/ksz8795_dt_ids +87 drivers/net/dsa/microchip/ksz8795_spi.c e66f840c08a237 Tristram Ha 2019-07-29 86 e66f840c08a237 Tristram Ha 2019-07-29 @87 static const struct of_device_id ksz8795_dt_ids[] = { e66f840c08a237 Tristram Ha 2019-07-29 88 { .compatible = "microchip,ksz8765" }, e66f840c08a237 Tristram Ha 2019-07-29 89 { .compatible = "microchip,ksz8794" }, e66f840c08a237 Tristram Ha 2019-07-29 90 { .compatible = "microchip,ksz8795" }, e66f840c08a237 Tristram Ha 2019-07-29 91 {}, e66f840c08a237 Tristram Ha 2019-07-29 92 }; e66f840c08a237 Tristram Ha 2019-07-29 93 MODULE_DEVICE_TABLE(of, ksz8795_dt_ids); e66f840c08a237 Tristram Ha 2019-07-29 94 :::::: The code at line 87 was first introduced by commit :::::: e66f840c08a237acfbb981592047b53e7411012f net: dsa: ksz: Add Microchip KSZ8795 DSA driver :::::: TO: Tristram Ha <Tristram.Ha(a)microchip.com&gt; :::::: CC: David S. Miller <davem(a)davemloft.net&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org