tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: cd1245d75ce93b8fd206f4b34eb58bcfe156d5e9 commit: 97e4910232fa1f81e806aa60c25a0450276d99a2 linux/compiler-clang.h: define HAVE_BUILTIN_BSWAP* date: 3 months ago config: powerpc-randconfig-r031-20210610 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project d2012d965d60c3258b3a69d024491698f8aec386) 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://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 97e4910232fa1f81e806aa60c25a0450276d99a2 # 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 warnings (new ones prefixed by >>): In file included from fs/reiserfs/do_balan.c:15: In file included from fs/reiserfs/reiserfs.h:10: In file included from include/linux/interrupt.h:11: In file included from include/linux/hardirq.h:10: In file included from arch/powerpc/include/asm/hardirq.h:6: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: 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>:96:1: 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 fs/reiserfs/do_balan.c:15: In file included from fs/reiserfs/reiserfs.h:10: In file included from include/linux/interrupt.h:11: In file included from include/linux/hardirq.h:10: In file included from arch/powerpc/include/asm/hardirq.h:6: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: 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>:98:1: 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 fs/reiserfs/do_balan.c:15: In file included from fs/reiserfs/reiserfs.h:10: In file included from include/linux/interrupt.h:11: In file included from include/linux/hardirq.h:10: In file included from arch/powerpc/include/asm/hardirq.h:6: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: 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>:100:1: 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 fs/reiserfs/do_balan.c:15: In file included from fs/reiserfs/reiserfs.h:10: In file included from include/linux/interrupt.h:11: In file included from include/linux/hardirq.h:10: In file included from arch/powerpc/include/asm/hardirq.h:6: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: 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>:102:1: 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 fs/reiserfs/do_balan.c:15: In file included from fs/reiserfs/reiserfs.h:10: In file included from include/linux/interrupt.h:11: In file included from include/linux/hardirq.h:10: In file included from arch/powerpc/include/asm/hardirq.h:6: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: 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>:104:1: 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)) ~~~~~~~~~~~~~~~~~~~~~^ static void balance_leaf_new_nodes(struct tree_balance *tb, ^ 8 warnings generated. vim +/balance_leaf_new_nodes +1220 fs/reiserfs/do_balan.c 9d496552b95e95 Jeff Mahoney 2014-04-23 1218 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1219 /* Fill new nodes that appear in place of S[0] */ 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 @1220 static void balance_leaf_new_nodes(struct tree_balance *tb, 27d0e5bc85f334 Jeff Mahoney 2014-08-04 1221 struct item_head * const ih, 27d0e5bc85f334 Jeff Mahoney 2014-08-04 1222 const char * const body, 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1223 struct item_head *insert_key, 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1224 struct buffer_head **insert_ptr, 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1225 int flag) 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1226 { 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1227 int i; 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1228 for (i = tb->blknum[0] - 2; i >= 0; i--) { b54b8c91841537 Jeff Mahoney 2014-04-23 1229 BUG_ON(flag != M_INSERT && flag != M_PASTE); 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1230 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1231 RFALSE(!tb->snum[i], 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1232 "PAP-12200: snum[%d] == %d. Must be > 0", i, 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1233 tb->snum[i]); 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1234 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1235 /* here we shift from S to S_new nodes */ 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1236 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1237 tb->S_new[i] = get_FEB(tb); 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1238 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1239 /* initialized block type and tree level */ 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1240 set_blkh_level(B_BLK_HEAD(tb->S_new[i]), DISK_LEAF_NODE_LEVEL); 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1241 b54b8c91841537 Jeff Mahoney 2014-04-23 1242 if (flag == M_INSERT) 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1243 balance_leaf_new_nodes_insert(tb, ih, body, insert_key, 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1244 insert_ptr, i); b54b8c91841537 Jeff Mahoney 2014-04-23 1245 else /* M_PASTE */ 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1246 balance_leaf_new_nodes_paste(tb, ih, body, insert_key, 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1247 insert_ptr, i); 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1248 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1249 memcpy(insert_key + i, leaf_key(tb->S_new[i], 0), KEY_SIZE); 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1250 insert_ptr[i] = tb->S_new[i]; 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1251 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1252 RFALSE(!buffer_journaled(tb->S_new[i]) 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1253 || buffer_journal_dirty(tb->S_new[i]) 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1254 || buffer_dirty(tb->S_new[i]), 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1255 "PAP-12247: S_new[%d] : (%b)", 19ef1229bc2e24 Jan Kara 2014-06-11 1256 i, tb->S_new[i]); 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1257 } 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1258 } 0080e9f9d3ac71 Jeff Mahoney 2014-04-23 1259 :::::: The code at line 1220 was first introduced by commit :::::: 0080e9f9d3ac717537dbd6db1fc8ef72ce0b9cc1 reiserfs: balance_leaf refactor, pull out balance_leaf{left, right, new_nodes, finish_node} :::::: TO: Jeff Mahoney <jeffm(a)suse.com&gt; :::::: CC: Jan Kara <jack(a)suse.cz&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org