tree: https://git.kernel.org/pub/scm/linux/kernel/git/kees/linux.git kspp/memcpy/next-20210618/v0 head: fd2aa2a169de8bde9502e7a2fc48cd03d4bfd996 commit: b44eff85708d836f39515789c036c5003dc34ec6 [59/82] fortify: Detect struct member overflows in memmove() config: i386-randconfig-a011-20210619 (attached as .config) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 reproduce (this is a W=1 build): # https://git.kernel.org/pub/scm/linux/kernel/git/kees/linux.git/commit/?id... git remote add kees https://git.kernel.org/pub/scm/linux/kernel/git/kees/linux.git git fetch --no-tags kees kspp/memcpy/next-20210618/v0 git checkout b44eff85708d836f39515789c036c5003dc34ec6 # save the attached .config to linux build tree make W=1 ARCH=i386 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 >>): ld: arch/x86/boot/compressed/misc.o: in function `.L221': ld: arch/x86/boot/compressed/misc.o: in function `bcj_flush': misc.c:(.text+0x18b0): undefined reference to `fortify_warn_write' ld: arch/x86/boot/compressed/vmlinux: hidden symbol `fortify_warn_write' isn't defined ld: final link failed: bad value --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org