P3081 R2 Core safety profiles for C++26

[wg21bot]

P3081R0 Core safety Profiles: Specification, adoptability, and impact (Herb Sutter)

[jfbastien]

SG15 and SG23: please consider and forward to EWG.

[Bigcheese]

SG15 wants to pursue normatively requiring implementations to offer some specific “Fix” semantics as described in P3081R0, such as “when type_safety profile is enabled, a static_cast pointer downcast remains static_cast in the source code but is interpreted as-if the code had written dynamic_cast” — SG15 will separately describe how implementations could conform

SF	F	N	A	SA
3	5	2	0	0

SG15 wants to pursue normatively requiring implementations to offer some specific “Modernize” fixits (as a new form of diagnostic) as described in P3081R0, such as “when type_safety profile is enabled, for a static_cast pointer downcast offer a mechanical fixit to change the source code into a dynamic_cast” — SG15 will separately describe how implementations could conform

SF	F	N	A	SA
2	6	2	0	0

[rogerorr]

P3081R0 was seen in SG23 on Thurs in Wroclaw

POLL: Apply the SG23 syntax decisions (Weds) in Wrocław and other SG23 direction to P3081R0, and forward P3081 to EWG as part of an initial set of Profiles targeting C++26.

Favor	Neutral	Against
23	1	0

[jfbastien]

Seen in EWG on Friday:

Poll: P3081r0 Core safety Profiles, we are interested in pursuing profiles in the C++26 timeline, including aspects of the specification which potentially have language and library impact (i.e. despite the P1000 schedule).

SF	F	N	A	SA
25	19	4	2	1

Result: consensus in favor

EWG will perform telecons (@hanickadot) between now and the next meeting to discuss individual profile aspects.

[hanickadot]

EWG seen first section of paper's wording on 2024/12/11 telecon and took (non-binding, temperature in the room) following polls:

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D3081R1: The profile attributes enforce and apply should be separated out from P3081 and done separately, leaving the initial version of profiles to just Implementation-Defined Translation-Unit level configuration.

SF	F	N	A	SA
6	10	10	1	1

Result: Consensus

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D3081R1: The next revision of P3081 should explore, clarify, and justify the application of profile attributes on lexical vs declaration scoping.

SF	F	N	A	SA
11	10	2	0	0

Result: Consensus

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D3081R1: EWG prefers that profile attributes include the profiles:: namespace.

SF	F	N	A	SA
1	3	12	7	3

Result: Not consensus