Hi! I've to recompile my kernel in order to install RTAI toolbox. Following the installation guide RTAI-TARGET-HOWTO.txt and RTAI-Lab-tutorial.pdf I patched the kernel (path: linux-2.6.17; kernel: RTAI-3.5). Then I configure the kernel using menuconfig. When I launch the commands: $ make clean && make && make modules_install && make install I got some warnings like in these: [...] CC arch/i386/kernel/cpu/centaur.o CC arch/i386/kernel/cpu/transmeta.o arch/i386/kernel/cpu/transmeta.c: In function 'init_transmeta': arch/i386/kernel/cpu/transmeta.c:12: warning: 'cpu_freq' may be used uninitialized in this function CC arch/i386/kernel/cpu/intel.o CC arch/i386/kernel/cpu/intel_cacheinfo.o [...] Untill the compilation termes with the following error message: [...] CHK include/linux/compile.h UPD include/linux/compile.h CC init/version.o LD init/built-in.o LD .tmp_vmlinux1 init/built-in.o: In function `try_name': /usr/src/linux/init/do_mounts.c:115: undefined reference to `__stack_chk_fail' init/built-in.o: In function `name_to_dev_t': /usr/src/linux/init/do_mounts.c:206: undefined reference to `__stack_chk_fail' init/built-in.o: In function `change_floppy': /usr/src/linux/init/do_mounts.c:363: undefined reference to `__stack_chk_fail' init/built-in.o: In function `mount_block_root': /usr/src/linux/init/do_mounts.c:321: undefined reference to `__stack_chk_fail' init/built-in.o: In function `do_header': /usr/src/linux/init/initramfs.c:206: undefined reference to `__stack_chk_fail' arch/i386/kernel/built-in.o:/usr/src/linux/arch/i386/kernel/ptrace.c:634: more undefined references to `__stack_chk_fail' follow make: *** [.tmp_vmlinux1] Error 1 I've left the full compiler output in errors-compil_kernel.txt. I'll be very gratefully for any help! Roberto Olmi