Re: [PATCH 12/43] kcsan: clang: retire CONFIG_KCSAN_KCOV_BROKEN

From: Mark Rutland
Date: Wed Dec 15 2021 - 09:43:54 EST


On Wed, Dec 15, 2021 at 02:39:43PM +0100, Marco Elver wrote:
> On Wed, 15 Dec 2021 at 14:33, Mark Rutland <mark.rutland@xxxxxxx> wrote:
> >
> > On Tue, Dec 14, 2021 at 05:20:19PM +0100, Alexander Potapenko wrote:
> > > kcov used to be broken prior to Clang 11, but right now that version is
> > > already the minimum required to build with KCSAN, that is why we don't
> > > need KCSAN_KCOV_BROKEN anymore.
> >
> > Just to check, how is that requirement enforced?
>
> HAVE_KCSAN_COMPILER will only be true with Clang 11 or later, due to
> no prior compiler having "-tsan-distinguish-volatile=1".

I see -- could we add wording to that effect into the commit messge?

> > I see the core Makefiles enforce 10.0.1+, but I couldn't spot an explicit
> > version dependency in Kconfig.kcsan.
> >
> > Otherwise, this looks good to me!
>
> I think 5.17 will be Clang 11 only, so we could actually revert
> ea91a1d45d19469001a4955583187b0d75915759:
> https://lkml.kernel.org/r/Yao86FeC2ybOobLO@archlinux-ax161
>
> I should resend that to be added to the -kbuild tree.

FWIW, that also works for me.

Thanks,
Mark.