Re: [PATCH v3 2/3] gianfar: Delete unnecessary variable initialisations in gfar_ethflow_to_filer_table()

From: David Miller
Date: Fri Jan 15 2016 - 11:43:01 EST


From: SF Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
Date: Fri, 15 Jan 2016 12:34:33 +0100

>>> +++ b/drivers/net/ethernet/freescale/gianfar_ethtool.c
>>> @@ -768,12 +768,12 @@ static void ethflow_to_filer_rules (struct gfar_private *priv, u64 ethflow)
>>> static int gfar_ethflow_to_filer_table(struct gfar_private *priv, u64 ethflow,
>>> u64 class)
>>> {
>>> - unsigned int last_rule_idx = priv->cur_filer_idx;
>>> + unsigned int last_rule_idx;
>>
>> This is a write only variable. We can just remove it.
>
> Can a static source code analysis tool like the software "http://smatch.sourceforge.net/";
> detect that such a variable is not read by this function implementation so far?

No, but a human can.

And a human should fully analyze any change he writes based upon static
analysis tool results.

I am going to be honest, and say that I am completely ignoring most of
your static checker patches. You don't put enough care and consideration
into them, and I really don't have time to waste on looking at something
like that.