Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Mon, 26 Apr 2021 14:24:50 +0200
From:   Marc Kleine-Budde <mkl@pengutronix.de>
To:     Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Cc:     wg@grandegger.com, davem@davemloft.net, kuba@kernel.org,
        linux-can@vger.kernel.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] can: softing: Remove redundant variable ptr
Message-ID: <20210426122450.v2qxdxjk52d5dh6o@pengutronix.de>
References: <1619431696-81853-1-git-send-email-jiapeng.chong@linux.alibaba.com>
MIME-Version: 1.0
Content-Type: multipart/signed; micalg=pgp-sha512;
        protocol="application/pgp-signature"; boundary="wznd2aj2syrjztbm"
Content-Disposition: inline
In-Reply-To: <1619431696-81853-1-git-send-email-jiapeng.chong@linux.alibaba.com>
Precedence: bulk


--wznd2aj2syrjztbm
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

On 26.04.2021 18:08:16, Jiapeng Chong wrote:
> Variable ptr is being assigned a value from a calculation
> however the variable is never read,=20
                       ^^^^^^^^^^^^^

This is not 100% correct.

The variable ptr is read from, see a line directly above the line this
patch removes.

> so this redundant variable can be removed.

This patch doesn't remove the variable.

> Cleans up the following clang-analyzer warning:
>=20
> drivers/net/can/softing/softing_main.c:279:3: warning: Value stored to
> 'ptr' is never read [clang-analyzer-deadcode.DeadStores].
>=20
> drivers/net/can/softing/softing_main.c:242:3: warning: Value stored to
> 'ptr' is never read [clang-analyzer-deadcode.DeadStores].

The clang warning is more precise: the value stored to ptr in the
calculations this patch removes is not used, so the calculation and the
assignment can be removed.

> Reported-by: Abaci Robot <abaci@linux.alibaba.com>
> Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
> ---
>  drivers/net/can/softing/softing_main.c | 2 --
>  1 file changed, 2 deletions(-)
>=20
> diff --git a/drivers/net/can/softing/softing_main.c b/drivers/net/can/sof=
ting/softing_main.c
> index c44f341..cfc1325 100644
> --- a/drivers/net/can/softing/softing_main.c
> +++ b/drivers/net/can/softing/softing_main.c
> @@ -239,7 +239,6 @@ static int softing_handle_1(struct softing *card)
>  				DPRAM_INFO_BUSSTATE2 : DPRAM_INFO_BUSSTATE]);
>  		/* timestamp */
>  		tmp_u32 =3D le32_to_cpup((void *)ptr);
> -		ptr +=3D 4;
>  		ktime =3D softing_raw2ktime(card, tmp_u32);
> =20
>  		++netdev->stats.rx_errors;
> @@ -276,7 +275,6 @@ static int softing_handle_1(struct softing *card)
>  		ktime =3D softing_raw2ktime(card, tmp_u32);
>  		if (!(msg.can_id & CAN_RTR_FLAG))
>  			memcpy(&msg.data[0], ptr, 8);
> -		ptr +=3D 8;
>  		/* update socket */
>  		if (cmd & CMD_ACK) {
>  			/* acknowledge, was tx msg */
> --=20
> 1.8.3.1
>=20
>

Marc

--=20
Pengutronix e.K.                 | Marc Kleine-Budde           |
Embedded Linux                   | https://www.pengutronix.de  |
Vertretung West/Dortmund         | Phone: +49-231-2826-924     |
Amtsgericht Hildesheim, HRA 2686 | Fax:   +49-5121-206917-5555 |

--wznd2aj2syrjztbm
Content-Type: application/pgp-signature; name="signature.asc"

-----BEGIN PGP SIGNATURE-----

iQEzBAABCgAdFiEEK3kIWJt9yTYMP3ehqclaivrt76kFAmCGsQ8ACgkQqclaivrt
76m4dwf+LEypbHlRV8Ln+xlJLnusE+7XBn4eX8MHwGCBJibJYNkhlDUd2+PpoeZ8
8UrAn5XQ8kwJisLJpxsftSUjInkIX4EZXUgJ1i6hVa/haYQbo7XYFD53kKH2WIJ6
4/XpYVfaJmei5D3NeBzC58uqE2TWaL5h9HSCHv+zoJAuJft7MPTQ3ZTFoDHmHulF
jATg5YS4m9nxYczQBk0WAmvT8QRQ3WWlZ5msG/PzY5Jg1pQEMTReRomhkpJXlDVy
v87lBV8bjyTnIhtpxbwBOdq9v6fZ8NqlwErC003ITHVr4ZBk25mhk2u6DBMVO1GW
y5jseqRG0gOPh81zxKmDF310SUP+2g==
=hxzG
-----END PGP SIGNATURE-----

--wznd2aj2syrjztbm--