Hi Vincent, kernel test robot noticed the following build errors: [auto build test ERROR on akpm-mm/mm-everything] [also build test ERROR on linus/master v6.7-rc4 next-20231206] [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#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Vincent-Mailhol/lib-test_bitops-add-compile-time-optimization-evaluations-assertions/20231130-182837 base: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything patch link: https://lore.kernel.org/r/20231130102717.1297492-1-mailhol.vincent%40wanadoo.fr patch subject: [PATCH v2] lib: test_bitops: add compile-time optimization/evaluations assertions config: hexagon-allmodconfig (https://download.01.org/0day-ci/archive/20231206/202312062158.60c1e6yt-lkp@xxxxxxxxx/config) compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project.git 4a5ac14ee968ff0ad5d2cc1ffa0299048db4c88a) reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231206/202312062158.60c1e6yt-lkp@xxxxxxxxx/reproduce) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Closes: https://lore.kernel.org/oe-kbuild-all/202312062158.60c1e6yt-lkp@xxxxxxxxx/ All errors (new ones prefixed by >>): >> lib/test_bitops.c:74:2: error: call to '__compiletime_assert_178' declared with 'error' attribute: BUILD_BUG_ON failed: !__builtin_constant_p(__test_expr) 74 | test_const_eval(__ffs(BIT(n)) == n); | ^ lib/test_bitops.c:59:2: note: expanded from macro 'test_const_eval' 59 | BUILD_BUG_ON(!__builtin_constant_p(__test_expr)); \ | ^ include/linux/build_bug.h:50:2: note: expanded from macro 'BUILD_BUG_ON' 50 | BUILD_BUG_ON_MSG(condition, "BUILD_BUG_ON failed: " #condition) | ^ include/linux/build_bug.h:39:37: note: expanded from macro 'BUILD_BUG_ON_MSG' 39 | #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg) | ^ note: (skipping 1 expansions in backtrace; use -fmacro-backtrace-limit=0 to see all) include/linux/compiler_types.h:423:2: note: expanded from macro '_compiletime_assert' 423 | __compiletime_assert(condition, msg, prefix, suffix) | ^ include/linux/compiler_types.h:416:4: note: expanded from macro '__compiletime_assert' 416 | prefix ## suffix(); \ | ^ <scratch space>:18:1: note: expanded from here 18 | __compiletime_assert_178 | ^ 1 error generated. vim +74 lib/test_bitops.c 62 63 static void test_bitops_const_eval(void) 64 { 65 /* 66 * On any supported optimization level (-O2, -Os) and if 67 * invoked with a compile-time constant argument, the compiler 68 * must be able to fold into a constant expression all the bit 69 * find functions. Namely: __ffs(), ffs(), ffz(), __fls(), 70 * fls() and fls64(). Otherwise, trigger a build bug. 71 */ 72 const int n = 10; 73 > 74 test_const_eval(__ffs(BIT(n)) == n); 75 test_const_eval(ffs(BIT(n)) == n + 1); 76 test_const_eval(ffz(~BIT(n)) == n); 77 test_const_eval(__fls(BIT(n)) == n); 78 test_const_eval(fls(BIT(n)) == n + 1); 79 test_const_eval(fls64(BIT_ULL(n)) == n + 1); 80 } 81 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki
