Hi Robin, First bad commit (maybe != root cause): tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: 1df27313f50a57497c1faeb6a6ae4ca939c85a7d commit: b4ceb4a5359ed1c9ba4a20acf3a70d4bbead3248 iommu: Tidy up Kconfig for SoC IOMMUs date: 8 months ago config: x86_64-randconfig-a013-20210317 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 50c7504a93fdb90c26870db8c8ea7add895c7725) 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 # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b4ceb4a5359ed1c9ba4a20acf3a70d4bbead3248 git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git git fetch --no-tags linus master git checkout b4ceb4a5359ed1c9ba4a20acf3a70d4bbead3248 # 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 All warnings (new ones prefixed by >>): >> drivers/gpu/drm/rockchip/analogix_dp-rockchip.c:457:34: warning: unused variable 'rockchip_dp_dt_ids' [-Wunused-const-variable] static const struct of_device_id rockchip_dp_dt_ids[] = { ^ 1 warning generated. -- >> drivers/gpu/drm/rockchip/rockchip_vop_reg.c:1029:34: warning: unused variable 'vop_driver_dt_match' [-Wunused-const-variable] static const struct of_device_id vop_driver_dt_match[] = { ^ 1 warning generated. vim +/rockchip_dp_dt_ids +457 drivers/gpu/drm/rockchip/analogix_dp-rockchip.c d9c900b0270a18 Yakir Yang 2016-06-29 456 9e32e16e9e989f Yakir Yang 2016-03-29 @457 static const struct of_device_id rockchip_dp_dt_ids[] = { d9c900b0270a18 Yakir Yang 2016-06-29 458 {.compatible = "rockchip,rk3288-dp", .data = &rk3288_dp }, 82872e42bb1501 Yakir Yang 2016-06-29 459 {.compatible = "rockchip,rk3399-edp", .data = &rk3399_edp }, 9e32e16e9e989f Yakir Yang 2016-03-29 460 {} 9e32e16e9e989f Yakir Yang 2016-03-29 461 }; 9e32e16e9e989f Yakir Yang 2016-03-29 462 MODULE_DEVICE_TABLE(of, rockchip_dp_dt_ids); 9e32e16e9e989f Yakir Yang 2016-03-29 463 :::::: The code at line 457 was first introduced by commit :::::: 9e32e16e9e989f2c4a11b377c5ed3e1c7be16cfb drm: rockchip: dp: add rockchip platform dp driver :::::: TO: Yakir Yang :::::: CC: Yakir Yang --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org