From: Nathan Chancellor <natechancellor@gmail.com>
To: Arnd Bergmann <arnd@arndb.de>
Cc: Nicolas Pitre <nico@fluxnic.net>,
Ard Biesheuvel <ard.biesheuvel@linaro.org>,
Nick Desaulniers <ndesaulniers@google.com>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
Stefan Agner <stefan@agner.ch>,
Russell King <linux@armlinux.org.uk>,
clang-built-linux <clang-built-linux@googlegroups.com>,
Linux ARM <linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH] ARM: xor-neon: Replace __GNUC__ checks with CONFIG_CC_IS_GCC
Date: Fri, 31 May 2019 17:28:58 -0700 [thread overview]
Message-ID: <20190601002858.GA89184@archlinux-epyc> (raw)
In-Reply-To: <CAK8P3a2pYp6aaOSrtHKbVW+hPbwgj1An6dWNd-YLJyR5otvU-A@mail.gmail.com>
On Fri, May 31, 2019 at 11:03:19PM +0200, Arnd Bergmann wrote:
> On Fri, May 31, 2019 at 10:06 PM 'Nick Desaulniers' via Clang Built
> Linux <clang-built-linux@googlegroups.com> wrote:
> >
> > On Fri, May 31, 2019 at 12:21 PM Arnd Bergmann <arnd@arndb.de> wrote:
> > > clang, I would suggest dropping your patch then, and instead adding
> >
> > I disagree. The minimum version of gcc required to build the kernel
> > is 4.6, so the comment about older versions of gcc is irrelevant and
> > should be removed.
>
> Sure, that's ok. It just feels wrong to remove a warning that points
> to a real problem that still exists and can be detected at the moment.
>
> If we think that clang-9 is going to be fixed before its release,
> the warning could be changed to test for that version as a minimum,
> and point to the bugzilla entry for more details.
>
> Arnd
I just tested the arm64 implementation and it shows the same warnings
about cost as arm.
However, I see a warning as something that can be resolved by the user.
The GCC warning's solution is to just use a newer version of GCC
(something fairly easily attainable). This new warning currently has no
solution other than don't use clang.
It is up to you and Nick but I would say unless we are going to
prioritize fixing this, we shouldn't add a warning for it. I'd say it is
more appropriate to fix it then add a warning saying upgrade to this
version to fix it, like the GCC one (though I don't necessarily hate
adding the warning assuming that clang 9 will have it fixed).
Cheers,
Nathan
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http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
WARNING: multiple messages have this Message-ID (diff)
From: Nathan Chancellor <natechancellor@gmail.com>
To: Arnd Bergmann <arnd@arndb.de>
Cc: Nick Desaulniers <ndesaulniers@google.com>,
Russell King <linux@armlinux.org.uk>,
Nicolas Pitre <nico@fluxnic.net>, Stefan Agner <stefan@agner.ch>,
Linux ARM <linux-arm-kernel@lists.infradead.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
Ard Biesheuvel <ard.biesheuvel@linaro.org>,
clang-built-linux <clang-built-linux@googlegroups.com>
Subject: Re: [PATCH] ARM: xor-neon: Replace __GNUC__ checks with CONFIG_CC_IS_GCC
Date: Fri, 31 May 2019 17:28:58 -0700 [thread overview]
Message-ID: <20190601002858.GA89184@archlinux-epyc> (raw)
In-Reply-To: <CAK8P3a2pYp6aaOSrtHKbVW+hPbwgj1An6dWNd-YLJyR5otvU-A@mail.gmail.com>
On Fri, May 31, 2019 at 11:03:19PM +0200, Arnd Bergmann wrote:
> On Fri, May 31, 2019 at 10:06 PM 'Nick Desaulniers' via Clang Built
> Linux <clang-built-linux@googlegroups.com> wrote:
> >
> > On Fri, May 31, 2019 at 12:21 PM Arnd Bergmann <arnd@arndb.de> wrote:
> > > clang, I would suggest dropping your patch then, and instead adding
> >
> > I disagree. The minimum version of gcc required to build the kernel
> > is 4.6, so the comment about older versions of gcc is irrelevant and
> > should be removed.
>
> Sure, that's ok. It just feels wrong to remove a warning that points
> to a real problem that still exists and can be detected at the moment.
>
> If we think that clang-9 is going to be fixed before its release,
> the warning could be changed to test for that version as a minimum,
> and point to the bugzilla entry for more details.
>
> Arnd
I just tested the arm64 implementation and it shows the same warnings
about cost as arm.
However, I see a warning as something that can be resolved by the user.
The GCC warning's solution is to just use a newer version of GCC
(something fairly easily attainable). This new warning currently has no
solution other than don't use clang.
It is up to you and Nick but I would say unless we are going to
prioritize fixing this, we shouldn't add a warning for it. I'd say it is
more appropriate to fix it then add a warning saying upgrade to this
version to fix it, like the GCC one (though I don't necessarily hate
adding the warning assuming that clang 9 will have it fixed).
Cheers,
Nathan
next prev parent reply other threads:[~2019-06-01 0:29 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-28 23:57 [PATCH] ARM: xor-neon: Replace __GNUC__ checks with CONFIG_CC_IS_GCC Nathan Chancellor
2019-05-28 23:57 ` Nathan Chancellor
2019-05-30 23:00 ` Nick Desaulniers
2019-05-30 23:00 ` Nick Desaulniers
2019-05-31 8:05 ` Arnd Bergmann
2019-05-31 8:05 ` Arnd Bergmann
2019-05-31 18:32 ` Nathan Chancellor
2019-05-31 18:32 ` Nathan Chancellor
2019-05-31 19:21 ` Arnd Bergmann
2019-05-31 19:21 ` Arnd Bergmann
2019-05-31 20:06 ` Nick Desaulniers
2019-05-31 20:06 ` Nick Desaulniers
2019-05-31 20:26 ` Nathan Chancellor
2019-05-31 20:26 ` Nathan Chancellor
2019-05-31 21:03 ` Arnd Bergmann
2019-05-31 21:03 ` Arnd Bergmann
2019-06-01 0:28 ` Nathan Chancellor [this message]
2019-06-01 0:28 ` Nathan Chancellor
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