P3516 R2 Uninitialized algorithms for relocation

[wg21bot]

P3516R0 Uninitialized algorithms for relocation (Louis Dionne, Giuseppe D’Angelo)

[inbal2l]

2025-02-11 Library Evolution Hagenberg Meeting

P3516R1: Uninitialized algorithms for relocation

2025-02-11 Library Evolution Hagenberg Minutes

Champion: Giuseppe D’Angelo / Louis Dionne
Chair: Inbal Levi / Andreas Weis
Minute Taker: Robert Leahy

Summary

POLL: We’re unhappy with the current names of the utility presented in P3516R1 (as may be misleading) and ask to explore alternative names.

SF	F	N	A	SA
0	4	2	10	9

Attendance: 26 (IP) + 8 (R)
Author's Position: 2xSA
Outcome: Consensus against

POLL: Support only non-throwing relocation (no-throw move CTORs types) (for which is_nothrow_relocatable = true) in the interface proposed in P3516R1

SF	F	N	A	SA
1	5	0	8	12

Attendance: 27 (IP) + 8 (R)
Author's Position: 2xSA
Outcome: Consensus against

POLL: Support only std::contiguous_iterators in the interface proposed in P3516R1.

SF	F	N	A	SA
0	4	0	13	4

Attendance: 27 (IP) + 8 (R)
Author's Position: 2xA
Outcome: Consensus against

POLL: Expose “relocate-at” interface to the users (remove the exposition only).

SF	F	N	A	SA
8	13	6	1	0

Attendance: 27 (IP) + 8 (R)
Author's Position: 2xSF
Outcome: Strong consensus in favor

ACTION: Explore the interface introduced by “relocate-at”, including exploring name alternatives.

ACTION: Modify in wording: Is_trivially_relocatable_v into is_nothrow_relocatable_throw

POLL: Add overloads which takes execution policy of the functions (to be consistent with P3179):

1. std::uninitialized_relocate
2. std::uninitialized_relocate_n
3. Std::uninitialized_relocate_backward

Make relocate-at non-exposition only function, and forward the updated revision P3516R2 to LWG for C++26.

SF	F	N	A	SA
10	12	5	0	0

Attendance: 26 (IP) + 7 (R)
Author's Position: 2xSF
Outcome: Strong consensus in favour

Next Steps

Apply changes above and forward the updated revision P3516R2 to LWG for C++26.