On Wed, Jan 13, 2021 at 08:39:52AM +0800, kernel test robot wrote: > Hi Nathan, > > I love your patch! Perhaps something to improve: > > [auto build test WARNING on 7c53f6b671f4aba70ff15e1b05148b10d58c2837] > > url: https://github.com/0day-ci/linux/commits/Nathan-Chancellor/ubsan-Implement-__ubsan_handle_alignment_assumption/20210113-055714 > base: 7c53f6b671f4aba70ff15e1b05148b10d58c2837 > config: arm64-randconfig-r031-20210112 (attached as .config) > compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 32bcfcda4e28375e5a85268d2acfabcfcc011abf) > 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 arm64 cross compiling tool for clang build > # apt-get install binutils-aarch64-linux-gnu > # https://github.com/0day-ci/linux/commit/775adad26a60878926c0ee6cd460a1375bbe51e6 > git remote add linux-review https://github.com/0day-ci/linux > git fetch --no-tags linux-review Nathan-Chancellor/ubsan-Implement-__ubsan_handle_alignment_assumption/20210113-055714 > git checkout 775adad26a60878926c0ee6cd460a1375bbe51e6 > # save the attached .config to linux build tree > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64 > > If you fix the issue, kindly add following tag as appropriate > Reported-by: kernel test robot <lkp@xxxxxxxxx> > > All warnings (new ones prefixed by >>): > > lib/ubsan.c:192:6: warning: no previous prototype for function '__ubsan_handle_add_overflow' [-Wmissing-prototypes] > void __ubsan_handle_add_overflow(void *data, > ^ > lib/ubsan.c:192:1: note: declare 'static' if the function is not intended to be used outside of this translation unit > void __ubsan_handle_add_overflow(void *data, > ^ > static > lib/ubsan.c:200:6: warning: no previous prototype for function '__ubsan_handle_sub_overflow' [-Wmissing-prototypes] > void __ubsan_handle_sub_overflow(void *data, > ^ > lib/ubsan.c:200:1: note: declare 'static' if the function is not intended to be used outside of this translation unit > void __ubsan_handle_sub_overflow(void *data, > ^ Given that these are compiler inserted functions, there is not much of a point to having prototypes to them. If people feel shutting these warnings up is worthwhile, we can just add the prototypes right above the function definition in a follow up patch. Cheers, Nathan
