[PATCH RFC] roll our own printf implementation

Denys Vlasenko dvlasenk at redhat.com
Mon Apr 16 16:26:19 UTC 2012


On 03/30/2012 10:08 PM, Denys Vlasenko wrote:
> On 03/30/2012 08:24 PM, Mike Frysinger wrote:
>> it's hard to say that having to add casts to arguments is an improvement. are
>> those really necessary?
>
> Casts are necessary only when you print chars or shorts -
> a rare operation. As you see, in the entire strace tree
> only four tprintf calls needed tweaking.
>
> Strictly speaking, casts may be not necessary - IIRC,
> variadic function arguments are auto-promoted to int anyway.
> But I prefer to not rely on my vague recollections
> of C standards - I'd use casts instead.
>
> It is possible to retain ability to understand %h[h]u,
> but is it worth slowing down every tprintf for just four
> cases where we use it?

I committed the code to git, but disabled it in defs.h -
it appears to be only a small speedup. Not worth exposing
users to possible bugs for it; however, if someone
wants to experiment, it's there...

-- 
vda






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