Re: printf %s with NULL pointer (was Re: BUG #17098: Assert failed on composing an error message when adding a type to an extension being dropped)

Em ter., 13 de jul. de 2021 às 11:29, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> escreveu:

> Laurenz Albe <laurenz(dot)albe(at)cybertec(dot)at> writes:
> > On Mon, 2021-07-12 at 13:20 -0400, Tom Lane wrote:
> >> So my feeling about this is that switching snprintf.c's behavior
> >> would produce some net gain in robustness for v12 and up, while
> >> not making things any worse for the older branches. I still hold
> >> to the opinion that we've already flushed out all the cases of
> >> passing NULL that we're likely to find via ordinary testing.
>
> > New cases could be introduced in the future and might remain undetected.
> > What about adding an Assert that gags on NULLs, but still printing them
> > as "(null)"? That would help find such problems in a debug build.
>
> I think you're missing my main point, which is that it seems certain that
> there are corner cases that do this *now*. I'm proposing that we redefine
> this as not being a crash case, full stop.
>
I agree with Laurenz Albe, that on Debug builds, *printf with NULL, must
crash.
On production builds, fine, printing (null).
This will put a little more pressure on support, "Hey what mean's (null) in
my logs?",
but it's ok.

regards,
Ranier Vilela