Hi Andy, I love your patch! Yet something to improve: [auto build test ERROR on spi/for-next] [also build test ERROR on linus/master v5.11 next-20210215] [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] url: https://github.com/0day-ci/linux/commits/Andy-Shevchenko/parport-Introduc... base: https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-next config: powerpc-randconfig-r034-20210215 (attached as .config) compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project c9439ca36342fb6013187d0a69aef92736951476) 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 powerpc cross compiling tool for clang build # apt-get install binutils-powerpc-linux-gnu # https://github.com/0day-ci/linux/commit/b436c5f6666ea5fb47d7b1826a66d4110... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Andy-Shevchenko/parport-Introduce-module_parport_driver-helper-macro/20210216-042909 git checkout b436c5f6666ea5fb47d7b1826a66d4110bb37072 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=powerpc If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): ^ arch/powerpc/include/asm/io.h:537:62: note: expanded from macro '__do_outl' #define __do_outl(val, port) writel(val,(PCI_IO_ADDR)_IO_BASE+port); ~~~~~~~~~~~~~~~~~~~~~^ In file included from drivers/spi/spi-lm70llp.c:19: In file included from include/linux/spi/spi.h:15: In file included from include/linux/scatterlist.h:9: In file included from arch/powerpc/include/asm/io.h:619: arch/powerpc/include/asm/io-defs.h:43:1: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] DEF_PCI_AC_NORET(insb, (unsigned long p, void *b, unsigned long c), ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET' __do_##name al; \ ^~~~~~~~~~~~~~ <scratch space>:205:1: note: expanded from here __do_insb ^ arch/powerpc/include/asm/io.h:556:56: note: expanded from macro '__do_insb' #define __do_insb(p, b, n) readsb((PCI_IO_ADDR)_IO_BASE+(p), (b), (n)) ~~~~~~~~~~~~~~~~~~~~~^ In file included from drivers/spi/spi-lm70llp.c:19: In file included from include/linux/spi/spi.h:15: In file included from include/linux/scatterlist.h:9: In file included from arch/powerpc/include/asm/io.h:619: arch/powerpc/include/asm/io-defs.h:45:1: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] DEF_PCI_AC_NORET(insw, (unsigned long p, void *b, unsigned long c), ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET' __do_##name al; \ ^~~~~~~~~~~~~~ <scratch space>:207:1: note: expanded from here __do_insw ^ arch/powerpc/include/asm/io.h:557:56: note: expanded from macro '__do_insw' #define __do_insw(p, b, n) readsw((PCI_IO_ADDR)_IO_BASE+(p), (b), (n)) ~~~~~~~~~~~~~~~~~~~~~^ In file included from drivers/spi/spi-lm70llp.c:19: In file included from include/linux/spi/spi.h:15: In file included from include/linux/scatterlist.h:9: In file included from arch/powerpc/include/asm/io.h:619: arch/powerpc/include/asm/io-defs.h:47:1: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] DEF_PCI_AC_NORET(insl, (unsigned long p, void *b, unsigned long c), ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET' __do_##name al; \ ^~~~~~~~~~~~~~ <scratch space>:209:1: note: expanded from here __do_insl ^ arch/powerpc/include/asm/io.h:558:56: note: expanded from macro '__do_insl' #define __do_insl(p, b, n) readsl((PCI_IO_ADDR)_IO_BASE+(p), (b), (n)) ~~~~~~~~~~~~~~~~~~~~~^ In file included from drivers/spi/spi-lm70llp.c:19: In file included from include/linux/spi/spi.h:15: In file included from include/linux/scatterlist.h:9: In file included from arch/powerpc/include/asm/io.h:619: arch/powerpc/include/asm/io-defs.h:49:1: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] DEF_PCI_AC_NORET(outsb, (unsigned long p, const void *b, unsigned long c), ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET' __do_##name al; \ ^~~~~~~~~~~~~~ <scratch space>:211:1: note: expanded from here __do_outsb ^ arch/powerpc/include/asm/io.h:559:58: note: expanded from macro '__do_outsb' #define __do_outsb(p, b, n) writesb((PCI_IO_ADDR)_IO_BASE+(p),(b),(n)) ~~~~~~~~~~~~~~~~~~~~~^ In file included from drivers/spi/spi-lm70llp.c:19: In file included from include/linux/spi/spi.h:15: In file included from include/linux/scatterlist.h:9: In file included from arch/powerpc/include/asm/io.h:619: arch/powerpc/include/asm/io-defs.h:51:1: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] DEF_PCI_AC_NORET(outsw, (unsigned long p, const void *b, unsigned long c), ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET' __do_##name al; \ ^~~~~~~~~~~~~~ <scratch space>:213:1: note: expanded from here __do_outsw ^ arch/powerpc/include/asm/io.h:560:58: note: expanded from macro '__do_outsw' #define __do_outsw(p, b, n) writesw((PCI_IO_ADDR)_IO_BASE+(p),(b),(n)) ~~~~~~~~~~~~~~~~~~~~~^ In file included from drivers/spi/spi-lm70llp.c:19: In file included from include/linux/spi/spi.h:15: In file included from include/linux/scatterlist.h:9: In file included from arch/powerpc/include/asm/io.h:619: arch/powerpc/include/asm/io-defs.h:53:1: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] DEF_PCI_AC_NORET(outsl, (unsigned long p, const void *b, unsigned long c), ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET' __do_##name al; \ ^~~~~~~~~~~~~~ <scratch space>:215:1: note: expanded from here __do_outsl ^ arch/powerpc/include/asm/io.h:561:58: note: expanded from macro '__do_outsl' #define __do_outsl(p, b, n) writesl((PCI_IO_ADDR)_IO_BASE+(p),(b),(n)) ~~~~~~~~~~~~~~~~~~~~~^ module_parport_driver(spi_lm70llp_drv); ^ include/linux/parport.h:315:34: note: expanded from macro 'module_parport_driver' module_driver(__parport_driver, parport_add_driver, parport_del_driver) ^ include/linux/parport.h:315:54: note: expanded from macro 'module_parport_driver' module_driver(__parport_driver, parport_add_driver, parport_del_driver) ^ drivers/spi/spi-lm70llp.c:323:1: note: did you mean 'parport_del_port'? include/linux/parport.h:315:54: note: expanded from macro 'module_parport_driver' module_driver(__parport_driver, parport_add_driver, parport_del_driver) ^ include/linux/parport.h:328:6: note: 'parport_del_port' declared here void parport_del_port(struct parport *); ^ 12 warnings and 2 errors generated. vim +/parport_add_driver +323 drivers/spi/spi-lm70llp.c 316 317 static struct parport_driver spi_lm70llp_drv = { 318 .name = DRVNAME, 319 .match_port = spi_lm70llp_attach, 320 .detach = spi_lm70llp_detach, 321 .devmodel = true, 322 }; 324 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org