* H. Peter Anvin <hpa@xxxxxxxxx> wrote: > On 07/15/2013 03:27 PM, Russell King - ARM Linux wrote: > > On Mon, Jul 15, 2013 at 03:16:12PM -0700, Andrew Morton wrote: > >> I've been thinking for a while that CONFIG_BUG=n is a pretty dumb thing > >> to do, and that maintaining it (and trying to fix the warnings it > >> produces) aren't worth the effort and that we should remove the whole > >> thing. Perhaps your patch changes that calculus, dunno. Please discuss. > > > > This isn't about introducing "CONFIG_BUG=n" - this is about making a > > kernel with CONFIG_BUG=n build without producing tonnes and tonnes of > > warnings, as it does today. It makes building randconfig pretty > > useless to find what could be more important warnings. > > > > Well, there are three alternatives here, right: > > 1. We can use unreachable(), which means that the compiler can assume it > never happens. AFAICS this is dangerous as it loses warnings and moves execution into la-la-land without any obvious sign at the C level. > 2. We can trap without metadata. This is what the patch does. > 3. We can trap with metadata (current CONFIG_BUG=y). That is still kept with the patch. > I am *guessing* this does 2, but it isn't clear. Yes, that's what it does - and I think it's the best of all worlds: Acked-by: Ingo Molnar <mingo@xxxxxxxxxx> (the crazies can keep a separate patch to remove even more of BUG() to win a K or two.) Thanks, Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
