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)

Laurenz Albe <laurenz.albe@cybertec.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.