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From: Thomas Gleixner <tglx@linutronix.de>
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To: Wake Liu <wakel@google.com>, Ingo Molnar <mingo@redhat.com>, Shuah Khan
 <shuah@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>, Darren Hart
 <dvhart@infradead.org>, Davidlohr Bueso <dave@stgolabs.net>, =?utf-8?Q?An?=
 =?utf-8?Q?dr=C3=A9?= Almeida
 <andrealmeid@igalia.com>, Wake Liu <wakel@google.com>,
 linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org
Subject: Re: [PATCH] kselftest: futex: Fix memset with zero size warning
In-Reply-To: <20251119030052.315502-1-wakel@google.com>
References: <20251119030052.315502-1-wakel@google.com>
Date: Thu, 20 Nov 2025 12:59:27 +0100
Message-ID: <871plslxsw.ffs@tglx>
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On Wed, Nov 19 2025 at 11:00, Wake Liu wrote:
> The `FIXTURE(args)` macro defines an empty `struct _test_data_args`,
> leading to `sizeof(struct _test_data_args)` evaluating to 0. This
> caused a build error due to a compiler warning on a `memset` call
> with a zero size argument.

Where is that memset? The only possibly related one I can find in the
kselftest harness is:

        if (sizeof(foo) > 0)
           memset(foo, 0, sizeof(foo));

If your compiler complains about that, then you need to fix your
compiler and not perfectly correct code.

You again fail to provide enough information to understand what you are
trying to "fix" including the compiler version and related built
options.

Thanks,

        tglx