Subject: Re: [PATCH linux-next] net/core: Remove unused assignment operations and variable

From: Simon Horman <[email-masked]>
Date: Wed, 20 Oct 2021 11:21:25 +0200

On Mon, Oct 18, 2021 at 09:13:56AM +0000, luo penghao wrote:
> From: penghao luo <[email-masked]>

I think the correct patch prefix for this patch would be:

[PATCH net-next] rtnetlink:

> Although if_info_size is assigned, it has not been used. And the variable
> should also be deleted.
> 
> The clang_analyzer complains as follows:
> 
> net/core/rtnetlink.c:3806: warning:
> 
> Although the value stored to 'if_info_size' is used in the enclosing expression,
> the value is never actually read from 'if_info_size'.
> 
> Reported-by: Zeal Robot <[email-masked]>
> Signed-off-by: penghao luo <[email-masked]>
> ---
>  net/core/rtnetlink.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
> index 327ca6b..52dc51a 100644
> --- a/net/core/rtnetlink.c
> +++ b/net/core/rtnetlink.c
> @@ -3804,9 +3804,9 @@ struct sk_buff *rtmsg_ifinfo_build_skb(int type, struct net_device *dev,
>  	struct net *net = dev_net(dev);
>  	struct sk_buff *skb;
>  	int err = -ENOBUFS;
> -	size_t if_info_size;
>  
> -	skb = nlmsg_new((if_info_size = if_nlmsg_size(dev, 0)), flags);
> +
> +	skb = nlmsg_new((if_nlmsg_size(dev, 0)), flags);

I think you can also drop the parentheses around the call to if_nlmsg_size.

>  	if (skb == NULL)
>  		goto errout;
> -- 
> 2.15.2