Hi Megha, FYI, the error/warning still remains. tree: https://github.com/changbae/Linux-kernel adl-po-presilicon head: 6173b90dca1633db3ad2ddb01b0825969c0aa8e3 commit: 79337cd8a283373ff6ebf8881a0761d442ccb287 [5619/9999] ims-msi: Add mask/unmask routines config: x86_64-randconfig-r002-20200619 (attached as .config) compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 487ca07fcc75d52755c9fe2ee05bcb3b6eeeec44) 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 79337cd8a283373ff6ebf8881a0761d442ccb287 # 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 >>, old ones prefixed by <<): void dev_ims_unmask_irq(struct irq_data *data) ^ drivers/base/ims-msi.c:53:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void dev_ims_unmask_irq(struct irq_data *data) ^ static drivers/base/ims-msi.c:129:20: warning: no previous prototype for function 'arch_create_ims_irq_domain' [-Wmissing-prototypes] struct irq_domain *arch_create_ims_irq_domain(struct irq_domain *parent, ^ drivers/base/ims-msi.c:129:1: note: declare 'static' if the function is not intended to be used outside of this translation unit struct irq_domain *arch_create_ims_irq_domain(struct irq_domain *parent, ^ static 2 warnings generated. vim +/dev_ims_unmask_irq +53 drivers/base/ims-msi.c 48 49 /** 50 * dev_msi_unmask_irq - Generic irq chip callback to unmask IMS interrupts 51 * @data: pointer to irqdata associated to that interrupt 52 */ 54 { 55 struct msi_desc *desc = irq_data_get_msi_desc(data); 56 57 desc->platform.masked = __dev_ims_desc_mask_irq(desc, 0); 58 } 59 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org