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Date:   Thu, 13 Oct 2022 19:31:59 -0600
From:   "Jason A. Donenfeld" <Jason@zx2c4.com>
To:     Nick Desaulniers <ndesaulniers@google.com>
Cc:     linux-toolchains@vger.kernel.org,
        Linux Kbuild mailing list <linux-kbuild@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: gcc 5 & 6 & others already out of date?
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On Thu, Oct 13, 2022 at 02:08:22PM -0700, Nick Desaulniers wrote:
> On Wed, Oct 12, 2022 at 6:37 PM Jason A. Donenfeld <Jason@zx2c4.com> wrote:
> >
> > Hi,
> >
> > I've been working on a (still in development) patch that tries to
> > apply a few compile-time constant folding tricks to a widely used
> > library function, so I wanted to make sure my trickery worked across
> > all supported gcc versions for as many call sites as possible.
> 
> I'd imagine the kernel's inconsistent use of -ffreestanding per
> architecture would be a blocker, if by library function you're
> referring to a symbol that would typically be provided by the libc?
> 
> Do you have more info about what the specific issue you've observed is?

As mentioned, I don't really care to follow up with this. But you can if
you want to waste your time. Download a toolchain. Run allmodconfig.
Observe breakage. Shrug your shoulders and wish we would sunset ancient
toolchains.

Jason