DPDK patches and discussions
 help / color / mirror / Atom feed
From: Andrew Rybchenko <arybchenko@solarflare.com>
To: Maxime Coquelin <maxime.coquelin@redhat.com>, <dev@dpdk.org>,
	<xiangxia.m.yue@gmail.com>, <ferruh.yigit@intel.com>,
	<thomas@monjalon.net>, <tredaelli@redhat.com>
Subject: Re: [dpdk-dev] [PATCH] vhost: fix build issue caused by unchecked returned values
Date: Fri, 30 Mar 2018 18:18:44 +0300	[thread overview]
Message-ID: <f77a17f5-c375-0c23-55fe-3cd16476b281@solarflare.com> (raw)
In-Reply-To: <20180330151641.20715-1-maxime.coquelin@redhat.com>

On 03/30/2018 06:16 PM, Maxime Coquelin wrote:
> This patch fixes below build issue seen with some compilers
> or build options:
>
> lib/librte_vhost/fd_man.c: In function ‘fdset_pipe_read_cb’:
> lib/librte_vhost/fd_man.c:284:2: error: ignoring return value of ‘read’, declared with attribute warn_unused_result [-Werror=unused-result]
>    read(readfd, charbuf, sizeof(charbuf));
>    ^
> lib/librte_vhost/fd_man.c: In function ‘fdset_pipe_notify’:
> lib/librte_vhost/fd_man.c:324:2: error: ignoring return value of ‘write’, declared with attribute warn_unused_result [-Werror=unused-result]
>    write(fdset->u.writefd, "1", 1);
>    ^
>
> Reported-by: Andrew Rybchenko <arybchenko@solarflare.com>
> Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
> Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
> ---
>   lib/librte_vhost/fd_man.c | 17 +++++++++++++++--
>   1 file changed, 15 insertions(+), 2 deletions(-)
>
> diff --git a/lib/librte_vhost/fd_man.c b/lib/librte_vhost/fd_man.c
> index ca1ba2622..1f9e22f96 100644
> --- a/lib/librte_vhost/fd_man.c
> +++ b/lib/librte_vhost/fd_man.c
> @@ -281,7 +281,13 @@ fdset_pipe_read_cb(int readfd, void *dat __rte_unused,
>   		   int *remove __rte_unused)
>   {
>   	char charbuf[16];
> -	read(readfd, charbuf, sizeof(charbuf));
> +	int r = read(readfd, charbuf, sizeof(charbuf));
> +	/*
> +	 * Just an optimization, we don't care if read() failed
> +	 * so ignore explicitly its return value to make the
> +	 * compiler happy
> +	 */
> +	RTE_SET_USED(r);
>   }
>   
>   void
> @@ -321,5 +327,12 @@ fdset_pipe_init(struct fdset *fdset)
>   void
>   fdset_pipe_notify(struct fdset *fdset)
>   {
> -	write(fdset->u.writefd, "1", 1);
> +	int r = write(fdset->u.writefd, "1", 1);
> +	/*
> +	 * Just an optimization, we don't care if read() failed

read() -> write()

> +	 * so ignore explicitly its return value to make the
> +	 * compiler happy
> +	 */
> +	RTE_SET_USED(r);
> +
>   }

  reply	other threads:[~2018-03-30 15:19 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-03-30 15:16 Maxime Coquelin
2018-03-30 15:18 ` Andrew Rybchenko [this message]
2018-03-30 15:21   ` Ferruh Yigit
2018-03-30 15:26     ` Maxime Coquelin
2018-03-30 15:31 ` Ferruh Yigit

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=f77a17f5-c375-0c23-55fe-3cd16476b281@solarflare.com \
    --to=arybchenko@solarflare.com \
    --cc=dev@dpdk.org \
    --cc=ferruh.yigit@intel.com \
    --cc=maxime.coquelin@redhat.com \
    --cc=thomas@monjalon.net \
    --cc=tredaelli@redhat.com \
    --cc=xiangxia.m.yue@gmail.com \
    /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).