Hi Venkata, FYI, the error/warning still remains. tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master head: 889bab4c367a0ef58208fd80fafa74bb6e2dca26 commit: ace4e30dbca706ec392b877b16031388366e2516 [3145/11714] Bluetooth: hci_qca: Add support for QTI Bluetooth chip wcn6750 config: arm-randconfig-r016-20210622 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project b3634d3e88b7f26534a5057bff182b7dced584fc) 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 arm cross compiling tool for clang build # apt-get install binutils-arm-linux-gnueabi # https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commi... git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git git fetch --no-tags linux-next master git checkout ace4e30dbca706ec392b877b16031388366e2516 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm 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 >>): drivers/bluetooth/hci_qca.c:1821:37: warning: unused variable 'qca_soc_data_wcn3990' [-Wunused-const-variable] static const struct qca_device_data qca_soc_data_wcn3990 = { ^ drivers/bluetooth/hci_qca.c:1832:37: warning: unused variable 'qca_soc_data_wcn3991' [-Wunused-const-variable] static const struct qca_device_data qca_soc_data_wcn3991 = { ^ drivers/bluetooth/hci_qca.c:1844:37: warning: unused variable 'qca_soc_data_wcn3998' [-Wunused-const-variable] static const struct qca_device_data qca_soc_data_wcn3998 = { ^ drivers/bluetooth/hci_qca.c:1855:37: warning: unused variable 'qca_soc_data_qca6390' [-Wunused-const-variable] static const struct qca_device_data qca_soc_data_qca6390 = { ^ static const struct qca_device_data qca_soc_data_wcn6750 = { ^ 5 warnings generated. vim +/qca_soc_data_wcn6750 +1860 drivers/bluetooth/hci_qca.c 1859 1861 .soc_type = QCA_WCN6750, 1862 .vregs = (struct qca_vreg []) { 1863 { "vddio", 5000 }, 1864 { "vddaon", 26000 }, 1865 { "vddbtcxmx", 126000 }, 1866 { "vddrfacmn", 12500 }, 1867 { "vddrfa0p8", 102000 }, 1868 { "vddrfa1p7", 302000 }, 1869 { "vddrfa1p2", 257000 }, 1870 { "vddrfa2p2", 1700000 }, 1871 { "vddasd", 200 }, 1872 }, 1873 .num_vregs = 9, 1874 .capabilities = QCA_CAP_WIDEBAND_SPEECH | QCA_CAP_VALID_LE_STATES, 1875 }; 1876 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org