On 01/15/2016 11:56 AM, kbuild test robot wrote: > tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master > head: 39750fe2d360d6f1ccdc6b33d0a5cb624c97a5fd > commit: df423af30988b62df3905601742b8948bbbce329 [11446/11650] UBSAN: run-time undefined behavior sanity checker > config: x86_64-randconfig-s5-01151613 (attached as .config) > reproduce: > git checkout df423af30988b62df3905601742b8948bbbce329 > # save the attached .config to linux build tree > make ARCH=x86_64 > > Note: it may well be a FALSE warning. FWIW you are at least aware of it now. > http://gcc.gnu.org/wiki/Better_Uninitialized_Warnings > Hmm.. UBSAN (and KASAN too) causes some maybe-uninitialized false positives. I'm not in favor of mucking different subsystems and initializing these variables as it brings some runtime overhead. So, perhaps we need turn off UBSAN/KASAN in all[yes|mod]config builds plus build with -Wno-maybe-uninitilized if any of those options enabled. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>