tree: https://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging.git hwmon-next head: 4fc1c17042661fa31212b561e0a59e3507760258 commit: 33e7d4ebc983b2f56f8f92c5b1b6f03eb20789ca [34/35] hwmon: (pmbus) Stop caching register values config: x86_64-randconfig-a013-20200909 (attached as .config) compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 0a5dc7effb191eff740e0e7ae7bd8e1f6bdb3ad9) 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 x86_64 cross compiling tool for clang build # apt-get install binutils-x86-64-linux-gnu git checkout 33e7d4ebc983b2f56f8f92c5b1b6f03eb20789ca # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 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 >>): } else if (!s1 || !s2) { ^~~~~~~~~~ drivers/hwmon/pmbus/pmbus_core.c:923:9: note: uninitialized use occurs here return ret; ^~~ drivers/hwmon/pmbus/pmbus_core.c:903:9: note: remove the 'if' if its condition is always false } else if (!s1 || !s2) { ^~~~~~~~~~~~~~~~~ } else if (!s1 || !s2) { ^~~ drivers/hwmon/pmbus/pmbus_core.c:923:9: note: uninitialized use occurs here return ret; ^~~ drivers/hwmon/pmbus/pmbus_core.c:903:13: note: remove the '||' if its condition is always false } else if (!s1 || !s2) { ^~~~~~ drivers/hwmon/pmbus/pmbus_core.c:885:9: note: initialize the variable 'ret' to silence this warning int ret, status; ^ = 0 2 warnings generated. # https://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging.git/... git remote add hwmon https://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging.git git fetch --no-tags hwmon hwmon-next git checkout 33e7d4ebc983b2f56f8f92c5b1b6f03eb20789ca vim +903 drivers/hwmon/pmbus/pmbus_core.c 442aba78728e77 drivers/hwmon/pmbus_core.c Guenter Roeck 2011-01-26 852 442aba78728e77 drivers/hwmon/pmbus_core.c Guenter Roeck 2011-01-26 853 /* 442aba78728e77 drivers/hwmon/pmbus_core.c Guenter Roeck 2011-01-26 854 * Return boolean calculated from converted data. 663834f3b796c0 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2013-01-20 855 * <index> defines a status register index and mask. 663834f3b796c0 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2013-01-20 856 * The mask is in the lower 8 bits, the register index is in bits 8..23. 442aba78728e77 drivers/hwmon/pmbus_core.c Guenter Roeck 2011-01-26 857 * 663834f3b796c0 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2013-01-20 858 * The associated pmbus_boolean structure contains optional pointers to two 663834f3b796c0 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2013-01-20 859 * sensor attributes. If specified, those attributes are compared against each 663834f3b796c0 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2013-01-20 860 * other to determine if a limit has been exceeded. 442aba78728e77 drivers/hwmon/pmbus_core.c Guenter Roeck 2011-01-26 861 * 663834f3b796c0 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2013-01-20 862 * If the sensor attribute pointers are NULL, the function returns true if 663834f3b796c0 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2013-01-20 863 * (status[reg] & mask) is true. 663834f3b796c0 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2013-01-20 864 * 663834f3b796c0 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2013-01-20 865 * If sensor attribute pointers are provided, a comparison against a specified 663834f3b796c0 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2013-01-20 866 * limit has to be performed to determine the boolean result. 442aba78728e77 drivers/hwmon/pmbus_core.c Guenter Roeck 2011-01-26 867 * In this case, the function returns true if v1 >= v2 (where v1 and v2 are 663834f3b796c0 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2013-01-20 868 * sensor values referenced by sensor attribute pointers s1 and s2). 442aba78728e77 drivers/hwmon/pmbus_core.c Guenter Roeck 2011-01-26 869 * 442aba78728e77 drivers/hwmon/pmbus_core.c Guenter Roeck 2011-01-26 870 * To determine if an object exceeds upper limits, specify <s1,s2> = <v,limit>. 442aba78728e77 drivers/hwmon/pmbus_core.c Guenter Roeck 2011-01-26 871 * To determine if an object exceeds lower limits, specify <s1,s2> = <limit,v>. 442aba78728e77 drivers/hwmon/pmbus_core.c Guenter Roeck 2011-01-26 872 * 442aba78728e77 drivers/hwmon/pmbus_core.c Guenter Roeck 2011-01-26 873 * If a negative value is stored in any of the referenced registers, this value 442aba78728e77 drivers/hwmon/pmbus_core.c Guenter Roeck 2011-01-26 874 * reflects an error code which will be returned. 442aba78728e77 drivers/hwmon/pmbus_core.c Guenter Roeck 2011-01-26 875 */ 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 876 static int pmbus_get_boolean(struct i2c_client *client, struct pmbus_boolean *b, 663834f3b796c0 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2013-01-20 877 int index) 442aba78728e77 drivers/hwmon/pmbus_core.c Guenter Roeck 2011-01-26 878 { 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 879 struct pmbus_data *data = i2c_get_clientdata(client); 663834f3b796c0 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2013-01-20 880 struct pmbus_sensor *s1 = b->s1; 663834f3b796c0 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2013-01-20 881 struct pmbus_sensor *s2 = b->s2; 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 882 u16 mask = pb_index_to_mask(index); 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 883 u8 page = pb_index_to_page(index); 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 884 u16 reg = pb_index_to_reg(index); d7ee11157f1fce drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2012-03-28 885 int ret, status; a66a6eb9db10bd drivers/hwmon/pmbus/pmbus_core.c Edward A. James 2017-08-10 886 u16 regval; 442aba78728e77 drivers/hwmon/pmbus_core.c Guenter Roeck 2011-01-26 887 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 888 mutex_lock(&data->update_lock); 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 889 status = pmbus_get_status(client, page, reg); 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 890 if (status < 0) { 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 891 ret = status; 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 892 goto unlock; 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 893 } 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 894 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 895 if (s1) 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 896 pmbus_update_sensor_data(client, s1); 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 897 if (s2) 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 898 pmbus_update_sensor_data(client, s2); 442aba78728e77 drivers/hwmon/pmbus_core.c Guenter Roeck 2011-01-26 899 442aba78728e77 drivers/hwmon/pmbus_core.c Guenter Roeck 2011-01-26 900 regval = status & mask; 663834f3b796c0 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2013-01-20 901 if (!s1 && !s2) { d7ee11157f1fce drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2012-03-28 902 ret = !!regval; 663834f3b796c0 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2013-01-20 @903 } else if (!s1 || !s2) { af78fdf4a61827 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2013-09-13 904 WARN(1, "Bad boolean descriptor %p: s1=%p, s2=%p\n", b, s1, s2); 663834f3b796c0 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2013-01-20 905 } else { 8ba75b20284967 drivers/hwmon/pmbus/pmbus_core.c Josh Lehan 2020-06-25 906 s64 v1, v2; 442aba78728e77 drivers/hwmon/pmbus_core.c Guenter Roeck 2011-01-26 907 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 908 if (s1->data < 0) { 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 909 ret = s1->data; 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 910 goto unlock; 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 911 } 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 912 if (s2->data < 0) { 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 913 ret = s2->data; 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 914 goto unlock; 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 915 } 442aba78728e77 drivers/hwmon/pmbus_core.c Guenter Roeck 2011-01-26 916 663834f3b796c0 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2013-01-20 917 v1 = pmbus_reg2data(data, s1); 663834f3b796c0 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2013-01-20 918 v2 = pmbus_reg2data(data, s2); d7ee11157f1fce drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2012-03-28 919 ret = !!(regval && v1 >= v2); 442aba78728e77 drivers/hwmon/pmbus_core.c Guenter Roeck 2011-01-26 920 } 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 921 unlock: 33e7d4ebc983b2 drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2020-09-04 922 mutex_unlock(&data->update_lock); d7ee11157f1fce drivers/hwmon/pmbus/pmbus_core.c Guenter Roeck 2012-03-28 923 return ret; 442aba78728e77 drivers/hwmon/pmbus_core.c Guenter Roeck 2011-01-26 924 } 442aba78728e77 drivers/hwmon/pmbus_core.c Guenter Roeck 2011-01-26 925 :::::: The code at line 903 was first introduced by commit :::::: 663834f3b796c0a118b84cf18c759f2c2aa537b6 hwmon: (pmbus) Improve boolean handling :::::: TO: Guenter Roeck <linux(a)roeck-us.net&gt; :::::: CC: Guenter Roeck <linux(a)roeck-us.net&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org