From: Ricardo Ribalda <ribalda@chromium.org>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
linux-perf-users@vger.kernel.org, Ingo Molnar <mingo@redhat.com>,
Arnaldo Carvalho de Melo <acme@kernel.org>
Subject: Re: [PATCH] tools/perf: Do not set a variable unless it will be used
Date: Fri, 4 Jun 2021 21:24:23 +0200 [thread overview]
Message-ID: <CANiDSCu4Brz7FZX5oa57kNLG9h_1EASX=bdQij4+apg0ZwW8QA@mail.gmail.com> (raw)
In-Reply-To: <YLn0D+1R2QHZYRVV@hirez.programming.kicks-ass.net>
Hi Peter
On Fri, 4 Jun 2021 at 11:36, Peter Zijlstra <peterz@infradead.org> wrote:
>
> On Fri, Jun 04, 2021 at 11:26:38AM +0200, Ricardo Ribalda wrote:
> > clang-13 triggers the following warning:
> >
> > bench/inject-buildid.c:351:6: error: variable 'len' set but not used [-Werror,-Wunused-but-set-variable]
> > u64 len = 0;
> >
> > This patch sets the value to len only if it will be used afterwards.
>
> My vote would be to kill that warning, what absolute shite.
My knowledge of llvm codebase is close to NULL, so it is much easier
for me to "fix" the code.
I would assume that the static analyser has found a magic condition
where the previous if always returns false, and has managed to
"optimize" the code.
--
Ricardo Ribalda
next prev parent reply other threads:[~2021-06-04 19:25 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-04 9:26 [PATCH] tools/perf: Do not set a variable unless it will be used Ricardo Ribalda
2021-06-04 9:36 ` Peter Zijlstra
2021-06-04 19:24 ` Ricardo Ribalda [this message]
2021-06-08 11:28 ` Peter Zijlstra
2021-06-09 14:15 ` Ricardo Ribalda
2021-06-08 11:12 ` David Laight
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