Hi Sinan, FYI, the error/warning still remains. tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: 28e8c4bc8eb483c22d977e147a0b98fc63efadf7 commit: 5d32a66541c4683456507481a0944ed2985e75c7 PCI/ACPI: Allow ACPI to be built without CONFIG_PCI set date: 13 days ago config: i386-alldefconfig (attached as .config) compiler: gcc-7 (Debian 7.3.0-1) 7.3.0 reproduce: git checkout 5d32a66541c4683456507481a0944ed2985e75c7 # save the attached .config to linux build tree make ARCH=i386 All errors (new ones prefixed by >>): drivers/acpi/device_sysfs.o: In function `description_show': >> device_sysfs.c:(.text+0x44b): undefined reference to `utf16s_to_utf8s' --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation