Hi Christoph, It's probably a bug fix that unveils the link errors. tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: df2fbf5bfa0e7fff8b4784507e4d68f200454318 commit: df41017eafd267c08acbfff99d34e4f96bbfbc92 ia64: remove support for machvecs date: 10 months ago :::::: branch date: 6 hours ago :::::: commit date: 10 months ago config: ia64-randconfig-r025-20200612 (attached as .config) compiler: ia64-linux-gcc (GCC) 9.3.0 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 git checkout df41017eafd267c08acbfff99d34e4f96bbfbc92 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=ia64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>, old ones prefixed by <<): ia64-linux-ld: arch/ia64/kernel/elfcore.o: in function `elf_core_write_extra_phdrs': ia64-linux-ld: arch/ia64/kernel/elfcore.o: in function `elf_core_write_extra_data': elfcore.c:(.text+0x2f2): undefined reference to `dump_emit' --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org _______________________________________________ kbuild mailing list -- kbuild(a)lists.01.org To unsubscribe send an email to kbuild-leave(a)lists.01.org