Re: [PATCH] fix: added new BANNED_EXPL macro for better error messages, new parameter

From: Taylor Blau <ttaylorr@github.com>
Date: Mar 8, 2021, 18:05 UTC
Message-ID: <YEZnaeJVt8Rk6duv@nand.local>
In-Reply-To: <xmqq7dmi8zym.fsf@gitster.c.googlers.com>

On Sun, Mar 07, 2021 at 12:34:57PM -0800, Junio C Hamano wrote:

Show 9 quoted lines

> "HG King via GitGitGadget" <gitgitgadget@gmail.com> writes:
>
> >  #undef strcpy
> > -#define strcpy(x,y) BANNED(strcpy)
> > +#define strcpy(x,y) BANNED_EXPL(strcpy, buffer_overflow_risk)
>
> That does not help programmers that much (the above does not say
> what to use instead, for example), and the mechanism inherently
> does not give you sufficient space to give helpful guidance.

Trying to cram information like "why is this function unsafe?" and "what function should I use instead?" seems ill-fitted to trying to a macro which is supposed to have a field for each.

I'm certainly not opposed to making these banned functions clearer, but I do not think that this is the way to do it.

> Adding a comment around each of these definition may be OK.  Upon
> seeing foo_is_a_banned_function, somebody new to the codebase would
> look for where it is banned, and find the above, so that is a good
> place to give guidance.

Perhaps, but all of this information is already covered accurately in the patches that introduced each banned function. So I'm not sure that I even agree that this information is difficult to discover to begin with, but I may be biased.

Thanks, Taylor