Hi David, kernel test robot noticed the following build warnings: [auto build test WARNING on drm-misc/drm-misc-next] [also build test WARNING on linux/master mkl-can-next/testing kdave/for-next akpm-mm/mm-nonmm-unstable axboe-block/for-next linus/master v6.8-rc6 next-20240226] [cannot apply to next-20240223 dtor-input/next dtor-input/for-linus horms-ipvs/master] [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/David-Laight/minmax-Put-all-the-clamp-definitions-together/20240226-005902 base: git://anongit.freedesktop.org/drm/drm-misc drm-misc-next patch link: https://lore.kernel.org/r/8657dd5c2264456f8a005520a3b90e2b%40AcuMS.aculab.com patch subject: [PATCH next v2 03/11] minmax: Simplify signedness check config: alpha-defconfig (https://download.01.org/0day-ci/archive/20240227/202402270937.9kmO5PFt-lkp@xxxxxxxxx/config) compiler: alpha-linux-gcc (GCC) 13.2.0 reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240227/202402270937.9kmO5PFt-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/202402270937.9kmO5PFt-lkp@xxxxxxxxx/ All warnings (new ones prefixed by >>): In file included from include/linux/kernel.h:28, from include/linux/cpumask.h:10, from include/linux/smp.h:13, from include/linux/lockdep.h:14, from include/linux/spinlock.h:63, from include/linux/swait.h:7, from include/linux/completion.h:12, from include/linux/crypto.h:15, from include/crypto/aead.h:13, from include/crypto/internal/aead.h:11, from crypto/skcipher.c:12: crypto/skcipher.c: In function 'skcipher_get_spot': >> include/linux/minmax.h:31:70: warning: ordered comparison of pointer with integer zero [-Wextra] 31 | (is_unsigned_type(typeof(x)) || (__is_constexpr(x) ? (x) + 0 >= 0 : 0)) | ^~ include/linux/minmax.h:39:11: note: in expansion of macro '__is_ok_unsigned' 39 | (__is_ok_unsigned(x) && __is_ok_unsigned(y))) | ^~~~~~~~~~~~~~~~ include/linux/minmax.h:49:24: note: in expansion of macro '__types_ok' 49 | _Static_assert(__types_ok(x, y), \ | ^~~~~~~~~~ include/linux/minmax.h:56:17: note: in expansion of macro '__cmp_once' 56 | __cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y))) | ^~~~~~~~~~ include/linux/minmax.h:70:25: note: in expansion of macro '__careful_cmp' 70 | #define max(x, y) __careful_cmp(max, x, y) | ^~~~~~~~~~~~~ crypto/skcipher.c:83:16: note: in expansion of macro 'max' 83 | return max(start, end_page); | ^~~ >> include/linux/minmax.h:31:70: warning: ordered comparison of pointer with integer zero [-Wextra] 31 | (is_unsigned_type(typeof(x)) || (__is_constexpr(x) ? (x) + 0 >= 0 : 0)) | ^~ include/linux/minmax.h:39:34: note: in expansion of macro '__is_ok_unsigned' 39 | (__is_ok_unsigned(x) && __is_ok_unsigned(y))) | ^~~~~~~~~~~~~~~~ include/linux/minmax.h:49:24: note: in expansion of macro '__types_ok' 49 | _Static_assert(__types_ok(x, y), \ | ^~~~~~~~~~ include/linux/minmax.h:56:17: note: in expansion of macro '__cmp_once' 56 | __cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y))) | ^~~~~~~~~~ include/linux/minmax.h:70:25: note: in expansion of macro '__careful_cmp' 70 | #define max(x, y) __careful_cmp(max, x, y) | ^~~~~~~~~~~~~ crypto/skcipher.c:83:16: note: in expansion of macro 'max' 83 | return max(start, end_page); | ^~~ vim +31 include/linux/minmax.h 9 10 /* 11 * min()/max()/clamp() macros must accomplish several things: 12 * 13 * - Avoid multiple evaluations of the arguments (so side-effects like 14 * "x++" happen only once) when non-constant. 15 * - Retain result as a constant expressions when called with only 16 * constant expressions (to avoid tripping VLA warnings in stack 17 * allocation usage). 18 * - Perform signed v unsigned type-checking (to generate compile 19 * errors instead of nasty runtime surprises). 20 * - Unsigned char/short are always promoted to signed int and can be 21 * compared against signed or unsigned arguments. 22 * - Unsigned arguments can be compared against non-negative signed constants. 23 * - Comparison of a signed argument against an unsigned constant fails 24 * even if the constant is below __INT_MAX__ and could be cast to int. 25 */ 26 #define __typecheck(x, y) \ 27 (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1))) 28 29 /* Allow unsigned compares against non-negative signed constants. */ 30 #define __is_ok_unsigned(x) \ > 31 (is_unsigned_type(typeof(x)) || (__is_constexpr(x) ? (x) + 0 >= 0 : 0)) 32 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki
