[kbuild-all] arch/mips/boot/compressed/../../lib/bswapsi.c:5:22: warning: no previous prototype for '__bswapsi2'

tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: 8ab774587903771821b59471cc723bba6d893942 commit: f78b25ee922ef6faf59a258af1b9388ca894cfd9 mips: decompressor: do not copy source files while building date: 5 days ago config: mips-loongson1b_defconfig (attached as .config) compiler: mipsel-linux-gcc (GCC) 11.2.0 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://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 f78b25ee922ef6faf59a258af1b9388ca894cfd9 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross ARCH=mips 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 arch/mips/boot/compressed/bswapsi.c:2: 5 | unsigned int notrace __bswapsi2(unsigned int u) | ^~~~~~~~~~ -- In file included from arch/mips/boot/compressed/ashldi3.c:2: 9 | long long notrace __ashldi3(long long u, word_type b) | ^~~~~~~~~ vim +/__bswapsi2 +5 arch/mips/boot/compressed/../../lib/bswapsi.c 1ee3630a3e57f3 Ralf Baechle 2015-09-29 4 aedcfbe06558a9 Harvey Hunt 2016-05-25 @5 unsigned int notrace __bswapsi2(unsigned int u) 1ee3630a3e57f3 Ralf Baechle 2015-09-29 6 { 1ee3630a3e57f3 Ralf Baechle 2015-09-29 7 return (((u) & 0xff000000) >> 24) | 1ee3630a3e57f3 Ralf Baechle 2015-09-29 8 (((u) & 0x00ff0000) >> 8) | 1ee3630a3e57f3 Ralf Baechle 2015-09-29 9 (((u) & 0x0000ff00) << 8) | 1ee3630a3e57f3 Ralf Baechle 2015-09-29 10 (((u) & 0x000000ff) << 24); 1ee3630a3e57f3 Ralf Baechle 2015-09-29 11 } 1ee3630a3e57f3 Ralf Baechle 2015-09-29 12 :::::: The code at line 5 was first introduced by commit :::::: aedcfbe06558a9f53002e82d5be64c6c94687726 MIPS: lib: Mark intrinsics notrace :::::: TO: Harvey Hunt <harvey.hunt(a)imgtec.com&gt; :::::: CC: Ralf Baechle <ralf(a)linux-mips.org&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org