2 is an aspect of 5. Breaking ABI is acceptable if it's deployable in some
way,.

On Sun, Nov 23, 2025, 11:14 organicoman via Std-Proposals <
std-proposals_at_[hidden]> wrote:

> That's true
> All proposal have 5 implicit stages for acceptance.
> 1- backward compatibility
> 2- ABI stability
> 3- effeciency (abstraction cost)
> 4- future extensibility.
> 5- time to adoption.
>
> And most of the proposal dies at stage 2.
>
>
>
>
>
> Sent from my Galaxy
>
>
> -------- Original message --------
> From: Andrey Semashev via Std-Proposals <std-proposals_at_[hidden]>
> Date: 11/23/25 11:52 AM (GMT+01:00)
> To: std-proposals_at_[hidden]
> Cc: Andrey Semashev <andrey.semashev_at_[hidden]>
> Subject: Re: [std-proposals] The most fair rant on C++
>
> On 23 Nov 2025 00:30, Thiago Macieira via Std-Proposals wrote:
> >
> > ABI is currently not part of the Standard.
>
> This is not entirely true. I'm sure you know that proposals and design
> decisions are evaluated with ABI stability in mind, and sometimes
> otherwise valid proposals are rejected (or not written in the first
> place) because they would break ABI.
>
> Just an example of this that I recently came upon:
>
> https://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#2094
>
> And this isn't just about the Standard, this affects implementations as
> well, and to even stronger degree.
>
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