CWG2538 Can standard attributes be syntactically ignored?

[jensmaurer]

See https://cplusplus.github.io/CWG/issues/2538.html

EWG discussed this in the context of P1774.
See also http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2022/p2552r0.pdf #1212

[erichkeane]

During discussions in the May 26, 2022 EWG meeting, we took the following polls related to CWG2538:

It is EWG's intent that [dcl.attr]/6 permits an implementation to completely ignore a standard attribute.

SF	F	N	A	SA
3	4	0	1	4

Result: Not Consensus

It is EWG's intent that [dcl.attr]/6 ONLY permits an implementation to ignore a standard attribute's effect, but not appertainment and argument parsing. See: CWG2538

SF	F	N	A	SA
2	6	3	0	2

Result: Consensus

The latter needs to be confirmed in Electronic Polling.

[jfbastien]

This was voted on in the June 2022 EWG polls. Results are here.

• 🗳 Poll: Resolve CWG2538 by clarifying that it is EWG’s intent that [dcl.attr]/6 ONLY permits an implementation to ignore a standard attribute’s effect, but not appertainment and argument parsing.

Poll votes:

SF	F	N	A	SA
11	6	4	0	3
Abstain: 4

Poll outcome: ❌ no consensus
Note: There is sufficient implementor pushback, some implementors also voting neutral, to override the otherwise positive support.

[jfbastien]

Discussed in Kona 2022 as an NB comment: https://github.com/cplusplus/nbballot/issues/430
It was accepted with modifications. Closing because of NB comment.
Remaining issues are being discussed under #1212