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References: <20231106-tcp-ao-fix-label-in-compound-statement-warning-v3-1-b54a64602a85@kernel.org>
In-Reply-To: <20231106-tcp-ao-fix-label-in-compound-statement-warning-v3-1-b54a64602a85@kernel.org>
From:   Eric Dumazet <edumazet@google.com>
Date:   Tue, 7 Nov 2023 04:44:12 +0100
Message-ID: <CANn89iKzVACROr7gzR2H3HPEQfVjctiXyiUswc-zyvN-06p3=Q@mail.gmail.com>
Subject: Re: [PATCH net v3] tcp: Fix -Wc23-extensions in tcp_options_write()
To:     Nathan Chancellor <nathan@kernel.org>
Cc:     davem@davemloft.net, dsahern@kernel.org, kuba@kernel.org,
        pabeni@redhat.com, ndesaulniers@google.com, trix@redhat.com,
        0x7f454c46@gmail.com, noureddine@arista.com, hch@infradead.org,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        llvm@lists.linux.dev, patches@lists.linux.dev
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On Mon, Nov 6, 2023 at 10:14=E2=80=AFPM Nathan Chancellor <nathan@kernel.or=
g> wrote:
>
> Clang warns (or errors with CONFIG_WERROR=3Dy) when CONFIG_TCP_AO is set:
>
>   net/ipv4/tcp_output.c:663:2: error: label at end of compound statement =
is a C23 extension [-Werror,-Wc23-extensions]
>     663 |         }
>         |         ^
>   1 error generated.
>
> On earlier releases (such as clang-11, the current minimum supported
> version for building the kernel) that do not support C23, this was a
> hard error unconditionally:
>
>
> Closes: https://github.com/ClangBuiltLinux/linux/issues/1953
> Fixes: 1e03d32bea8e ("net/tcp: Add TCP-AO sign to outgoing packets")
> Signed-off-by: Nathan Chancellor <nathan@kernel.org>
> ---
> Changes in v3:
> - Don't use a pointer to a pointer for ptr parameter to avoid the extra
>   indirection in process_tcp_ao_options(), just return the modified ptr
>   value back to the caller (Eric)

SGTM thanks.
Reviewed-by: Eric Dumazet <edumazet@google.com>