Re: [PATCH] string: Improve the generic strlcpy() implementation

[Ingo Molnar <mingo@kernel.org>]

* Linus Torvalds <torvalds@linux-foundation.org> wrote:

> So I don't think a "generic" range check helper can force types like
> "unsigned long".

Yeah.

> That said, doing a simple
> 
>     git grep '<.*||.*>'
> 
> does show that the "positive or non-zero ranges with constant range
> limits" case is fairly common, and maybe we could have a macro that
> does some magic compile-time checking that (a) the range really is a
> compile-time constant and (b) that range is valid and (c) avoids the
> comparison with zero if the expression to be tested is unsigned.
> 
> So it is possible that we could enable type limit checking if we also
> introduce a good way to not then create crap patches that actually
> make the code more fragile or less readable. I'm not violently against
> that. But I *am* violently against introducing that braindead warning
> without very clear rules that we don't then have the mindless and
> wrong changes to remove proper and obvious range checking and replace
> it with "the expression is unsigned so we remove the nice readable
> lower bounds check as unnecessary".

Ok, and fully agreed.

Thanks,

	Ingo