On Thu, Dec 3, 2020 at 1:44 AM Kees Cook <keescook@xxxxxxxxxxxx> wrote: > > With UBSAN_OBJECT_SIZE disabled for GCC, only UBSAN_ALIGNMENT remained > a noisy UBSAN option. Disable it for COMPILE_TEST so the rest of UBSAN > can be used for full all*config builds or other large combinations. > > Link: https://lore.kernel.org/lkml/CAHk-=wgXW=YLxGN0QVpp-1w5GDd2pf1W-FqY15poKzoVfik2qA@xxxxxxxxxxxxxx/ > Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> Have you checked if this has a notable impact on allmodconfig compile speed with gcc or clang? I think I've seen significant increases in build times before with this, but I don't remember the actual magnitude. Making it 20% slower would probably be ok, but making it twice as slow might be too much. Arnd
