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Date:   Fri, 10 Jun 2022 01:03:36 +0200 (CEST)
From:   Jan Engelhardt <jengelh@inai.de>
To:     Bill Wendling <morbo@google.com>
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Subject: Re: [PATCH 00/12] Clang -Wformat warning fixes
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On Friday 2022-06-10 00:49, Bill Wendling wrote:
>On Thu, Jun 9, 2022 at 3:25 PM Andrew Morton <akpm@linux-foundation.org> wrote:
>> On Thu,  9 Jun 2022 22:16:19 +0000 Bill Wendling <morbo@google.com> wrote:
>>
>> > This patch set fixes some clang warnings when -Wformat is enabled.
>>
>> tldr:
>>
>> -       printk(msg);
>> +       printk("%s", msg);
>>
>> Otherwise these changes are a
>> useless consumer of runtime resources.
>
>Calling a "printf" style function is already insanely expensive.
>[...]
>The "printk" and similar functions all have the "__printf" attribute.
>I don't know of a modification to that attribute which can turn off
>this type of check.

Perhaps you can split vprintk_store in the middle (after the call to
vsnprintf), and offer the second half as a function of its own (e.g.
"puts"). Then the tldr could be

- printk(msg);
+ puts(msg);