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Re: [std-proposals] vector::push_back must not invalidate past-the-end iterator

From: Barry Revzin <barry.revzin_at_[hidden]>
Date: Mon, 8 Dec 2025 15:20:03 -0600
On Mon, Dec 8, 2025 at 2:19 PM Brian Bi via Std-Proposals <
std-proposals_at_[hidden]> wrote:

> I'm going to try to be empathetic. The standardization process is a lot of
> work to get through. One of the unfortunate realities is that, even if it
> feels obvious that there is something additional the standard can
> guarantee---because it is already true on all implementations and there is
> no legitimate reason to ever create an implementation where it isn't
> true---that does not mean there's some quick process to get that guarantee
> into the standard. You still have to write a paper and present it at a
> meeting. And, in doing so, you might discover that what you thought was
> true (that there is no legitimate reason for keeping it UB) is not true
> after all, because someone else presents an argument that you hadn't
> considered.
>
> And nowadays (maybe you don't like it, but it is the reality) there are a
> lot of folks who feel that removing UB is not by itself sufficient
> motivation because, in their view, giving sanitizers permission to diagnose
> a questionable operation is more helpful to the programmer than making the
> operation defined. That does not mean that we cannot remove UB, but it does
> mean you have to come in with some kind of positive motivation for defining
> the UB, not just "we should do this because we can".
>
> Participating in standardization is a lot of hard work and it's totally
> understandable that a lot of people feel that the amount of effort required
> is disproportionate. That's why we have a few hundred people who come to
> meetings rather than thousands.
>

I'm going to not to be empathetic: it actually does not take very much
effort at all to motivate the existence of a problem.

The OP so far has simply pointed out that something does not work. I
haven't seen any attempt to articulate why it *should *work. Just a
statement that it should, and increasingly antagonistic refusals to
elaborate further. It's not even that I disagree with OP's argument that
this is worth changing, I disagree with the premise that OP has even made
an argument. If it's not worth OP's time to fully motivate a change, why is
it worth any of our time to discuss it?

Barry

Received on 2025-12-08 21:20:19