From: Petr Machata <me@pmachata.org>
To: Stephen Hemminger <stephen@networkplumber.org>
Cc: netdev@vger.kernel.org
Subject: Re: [PATCH iproute2 3/5] ss: fix warning about empty if()
Date: Thu, 29 Jun 2023 15:14:27 +0200 [thread overview]
Message-ID: <87pm5ee699.fsf@nvidia.com> (raw)
In-Reply-To: <20230628233813.6564-4-stephen@networkplumber.org>
Stephen Hemminger <stephen@networkplumber.org> writes:
> With all warnings enabled gcc wants brackets around the
> empty if() clause. "Yes I really want an empty clause"
>
> Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
> ---
> misc/ss.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/misc/ss.c b/misc/ss.c
> index de02fccb539b..e9d813596b91 100644
> --- a/misc/ss.c
> +++ b/misc/ss.c
> @@ -627,8 +627,9 @@ static void user_ent_hash_build_task(char *path, int pid, int tid)
>
> fp = fopen(stat, "r");
> if (fp) {
> - if (fscanf(fp, "%*d (%[^)])", task) < 1)
> + if (fscanf(fp, "%*d (%[^)])", task) < 1) {
> ; /* ignore */
> + }
> fclose(fp);
> }
> }
Reviewed-by: Petr Machata <me@pmachata.org>
As an aside, this whole if business is necessary in the first place due
to __attribute__((warn_unused_result)) that fscanf apparently has on
some libc's. But ignoring fscanf failures is safe, because a) `task' is
pre-initialized at variable definition, so ignoring the result like this
should indeed be safe; and b), fp references some file in /proc and we
can rely on the format and that the scan will in fact not fail.
next prev parent reply other threads:[~2023-06-29 13:40 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-06-28 23:38 [PATCH iproute2 0/5] Warning fixes Stephen Hemminger
2023-06-28 23:38 ` [PATCH iproute2 1/5] dcb: fully initialize flag table Stephen Hemminger
2023-06-29 13:08 ` Petr Machata
2023-06-28 23:38 ` [PATCH iproute2 2/5] fix fallthrough warnings Stephen Hemminger
2023-06-29 13:54 ` Petr Machata
2023-06-28 23:38 ` [PATCH iproute2 3/5] ss: fix warning about empty if() Stephen Hemminger
2023-06-29 13:14 ` Petr Machata [this message]
2023-06-28 23:38 ` [PATCH iproute2 4/5] ct: check for invalid proto Stephen Hemminger
2023-06-29 13:44 ` Petr Machata
2023-06-28 23:38 ` [PATCH iproute2 5/5] ifstat: fix warning about conditional Stephen Hemminger
2023-06-29 13:49 ` Petr Machata
2023-06-29 16:10 ` [PATCH iproute2 0/5] Warning fixes patchwork-bot+netdevbpf
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=87pm5ee699.fsf@nvidia.com \
--to=me@pmachata.org \
--cc=netdev@vger.kernel.org \
--cc=stephen@networkplumber.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).