Re: [Linux-6.11-rc4] perf BROKEN with LLVM/Clang 19.1.0-rc3

[Arnaldo Carvalho de Melo <acme@kernel.org>]

On Thu, Aug 22, 2024 at 01:11:22PM -0700, Namhyung Kim wrote:
> On Thu, Aug 22, 2024 at 11:20 AM Arnaldo Carvalho de Melo
> <acme@kernel.org> wrote:
> >
> > On Thu, Aug 22, 2024 at 11:17:21AM -0700, Namhyung Kim wrote:
> > > > On Thu, Aug 22, 2024 at 7:40 PM Arnaldo Carvalho de Melo
> > > > <acme@kernel.org> wrote:
> > > > > From 155212c965b5b23a90b8558449dbfd1c60dad934 Mon Sep 17 00:00:00 2001
> > > > > From: Arnaldo Carvalho de Melo <acme@redhat.com>
> > > > > Date: Thu, 22 Aug 2024 14:13:49 -0300
> > > > > Subject: [PATCH 1/1] perf python: Disable -Wno-cast-function-type-mismatch if
> > > > >  present on clang
> > > > >
> > > > > The -Wcast-function-type-mismatch option was introduced in clang 19 and
> > > > > its enabled by default, since we use -Werror, and python bindings do
> > > > > casts that are valid but trips this warning, disable it if present.
> > > > >
> > > > > Reported-by: Sedat Dilek <sedat.dilek@gmail.com>
> > > > > Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
> > > > > Cc: Ian Rogers <irogers@google.com>
> > > > > Cc: Ingo Molnar <mingo@redhat.com>
> > > > > Cc: Namhyung Kim <namhyung@kernel.org>
> > > > > Cc: Nathan Chancellor <nathan@kernel.org>
> > > > > Cc: Peter Zijlstra <peterz@infradead.org>
> > > > > Link: https://lore.kernel.org/lkml/CA+icZUVtHn8X1Tb_Y__c-WswsO0K8U9uy3r2MzKXwTA5THtL7w@mail.gmail.com
> > > > > Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
> > >
> > > Can we also add 'Fixes' tag to make this picked by stable kernels?
> >
> > Fixes what? This isn't a regression, clang 19 isn't available for Fedora
> > 40, the most recent.
> 
> No, I'm not saying it's a bug.  But we may want to build the old
> source code using new clang.

Sure, and with the tags we have now, we can signal it by using Closes:
and Cc: stable@kernel.org, without a version, I added those, the tags
section then is this:

    Closes: https://lore.kernel.org/all/CA+icZUXoJ6BS3GMhJHV3aZWyb5Cz2haFneX0C5pUMUUhG-UVKQ@mail.gmail.com
    Reported-by: Sedat Dilek <sedat.dilek@gmail.com>
    Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
    Cc: Ian Rogers <irogers@google.com>
    Cc: Ingo Molnar <mingo@redhat.com>
    Cc: Namhyung Kim <namhyung@kernel.org>
    Cc: Nathan Chancellor <nathan@kernel.org>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: stable@vger.kernel.org # To allow building with the upcoming clang 19
    Link: https://lore.kernel.org/lkml/CA+icZUVtHn8X1Tb_Y__c-WswsO0K8U9uy3r2MzKXwTA5THtL7w@mail.gmail.com
    Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Ok?

- Arnaldo