From: Yonghong Song <yhs@meta.com>
To: "Daniel T. Lee" <danieltimlee@gmail.com>,
Daniel Borkmann <daniel@iogearbox.net>,
Alexei Starovoitov <ast@kernel.org>,
Andrii Nakryiko <andrii.nakryiko@gmail.com>,
Yonghong Song <yhs@fb.com>
Cc: bpf@vger.kernel.org, netdev@vger.kernel.org
Subject: Re: [bpf-next 3/3] samples/bpf: fix uninitialized warning with test_current_task_under_cgroup
Date: Sat, 17 Dec 2022 09:49:31 -0800 [thread overview]
Message-ID: <c0d20556-cfb2-ed5e-3aa3-af34bb348b5b@meta.com> (raw)
In-Reply-To: <20221217153821.2285-4-danieltimlee@gmail.com>
On 12/17/22 7:38 AM, Daniel T. Lee wrote:
> Currently, compiling samples/bpf with LLVM warns about the uninitialized
> use of variable with test_current_task_under_cgroup.
>
> ./samples/bpf/test_current_task_under_cgroup_user.c:57:6:
> warning: variable 'cg2' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
> if (setup_cgroup_environment())
> ^~~~~~~~~~~~~~~~~~~~~~~~~~
> ./samples/bpf/test_current_task_under_cgroup_user.c:106:8:
> note: uninitialized use occurs here
> close(cg2);
> ^~~
> ./samples/bpf/test_current_task_under_cgroup_user.c:57:2:
> note: remove the 'if' if its condition is always false
> if (setup_cgroup_environment())
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> ./samples/bpf/test_current_task_under_cgroup_user.c:19:9:
> note: initialize the variable 'cg2' to silence this warning
> int cg2, idx = 0, rc = 1;
> ^
> = 0
> 1 warning generated.
>
> This commit resolve this compiler warning by pre-initialize the variable
> with error for safeguard.
>
> Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Acked-by: Yonghong Song <yhs@fb.com>
next prev parent reply other threads:[~2022-12-17 17:49 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-12-17 15:38 [bpf-next 0/3] samples/bpf: fix LLVM compilation warning with Daniel T. Lee
2022-12-17 15:38 ` [bpf-next 1/3] samples/bpf: remove unused function with test_lru_dist Daniel T. Lee
2022-12-17 17:48 ` Yonghong Song
2022-12-17 15:38 ` [bpf-next 2/3] samples/bpf: replace meaningless counter with tracex4 Daniel T. Lee
2022-12-17 17:49 ` Yonghong Song
2022-12-17 15:38 ` [bpf-next 3/3] samples/bpf: fix uninitialized warning with test_current_task_under_cgroup Daniel T. Lee
2022-12-17 17:49 ` Yonghong Song [this message]
2022-12-17 17:48 ` [bpf-next 0/3] samples/bpf: fix LLVM compilation warning with Yonghong Song
2022-12-18 0:08 ` Daniel T. Lee
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