2026 Telecons - cplusplus/LEWG GitHub Wiki

First 2026 telecon!
P3826R3: Fix or Remove Sender Algorithm Customization
(Discuss: US-207, FI-331, CA-358, FR-031, US 202)

Reflection
US 49-090: 13.2 [temp.param] Add "is_structural_type" query facility to the library P3856
US 82-145: [meta.const.eval] Extend std::is_within_lifetime (Adopt P3450)
FR-013-159: 21.4.1 [meta.syn] Facilitate the implementations of meta::members_of
AT 5-183 : 21.4.15p11 [meta.reflection.array] Consistently use std::array return type for reflect_constant_array
US 90-197: 21.4.3p4-5 [meta.define.static] Return reference (not pointer) from define_static_object P3739

Reflection Overflow
US 93-200: 21.4.6 [meta.reflection.names] Add has_source_location query
US 98-204: 21.4.7p26 [meta.reflection.queries] Replace is_complete_type with throwing assert_is_complete
FR-014-160: 21.4.1 [meta.syn] string_view, span, string, and vector should be structural types

(non) constexpr uncaught_exceptions and current_exception / Trivially copyable / std::atomic_ref::address
US 67-118: 17.9.2, 17.9.6 [support.exception] Do not make uncaught_exceptions() and current_exception() constexpr (and duplicates: PL-012,GB 03-119, DE-120, FI-121) (Paper "P3842R0: A conservative fix for constexpr uncaught_exceptions() and current_exception()" express intent).
US 135-216: 22.8.6.4p2, 5 [expected.object.assign] expected should be trivially copyable as appropriate
US 136-217: 22.8.7.4p1, 4 [expected.void.assign] expected<void, E> should be trivially copyable as appropriate
P3960R0: Define copy-constructibility-from-bytes (alternative approach)
US 132-211: 22.3.2p20, 23, 32, 36 [pairs.pair] pair should be trivially copyable as appropriate
US 133-212: 22.4.4.3p2, 5, 8, 12 [tuple.assign] tuple should be trivially copyable as appropriate
FR-030-310: 32.5.7.2 [atomics.ref.ops] std::atomic_ref::address should return uintptr_t (P3936)

Task Type
US 261-391: 33.13.6.5p3, 16, 17 [task.promise] Bad specification of parameter type
US 254-385: 33.13.6.5 [task.promise] Constraint allocator_arg argument to be the first argument LWG4334
US 255-384: 33.13.6.5 [task.promise] Use allocator from receiver's environment LWG4335 (Paper: P3980R0)
US 238-368: 33.13.5 [exec.task.scheduler] Allow customizations when using task_scheduler LWG4336 (SG1 recommended rejection, P3927R0 is a later paper contains new information)

reserve_hint
FR-023-244: 25 [ranges] Adopt P3763 Remove redundant reserve_hint members from view classes (Paper: P3763R1)
Hive
CZ 1-231: 23.3.8 [hive] make std::hive constexpr (Paper: P3933R0, comments from author: P3945R0)
US 143-238: 23.3.9.3p9 [hive.capacity] Tighten specification for shrink_to_fit and reshape
US 144-237: 23.3.9.3p9 [hive.capacity] shrink_to_fit and reshape should return reallocation indication
US 142-236: 23.3.9.3p4 [hive.capacity] reserve(n) gap between postconditions and throws (LWG Issue: LWG4379)

(NOTE: 1H later!)

inplace_vector
PL-006: 23.3.16.1 [inplace.vector.overview] Change the return type of inplace_vector try_push_back and try_emplace_back functions to optional (P3981)
US 150-228: 23.3.16.5p8-14 [inplace.vector.modifiers] try_push_back should be revised to use const optional<&>
GB 08-225: 23.3.16 [inplace.vector] try_emplace_back and try_push_back should return optional
US 68-122: 17.9.7p13-15 [propagation] return optional<T&> from exception_ptr_cast (P3739)
US 149-226: 23.3.16 [inplace.vector] Do not redesign std::inplace_vector inplace_vector

C++26 (feedback only, no binding decisions)
P3982R0: Fix meaning of strided_slice::extent for C++26 (related to PL-007: 23.7.3.7 [mdspan.sub] [mdspan.sub] Define the extent member of the strided_slice)
C++29
P3724R3: Integer division (Seen by SG6)

Last telecon before UK (C++29)
P3791R0: constexpr (deterministic) random
P3969R0: Fixing std::bit_cast of types with padding bits

(Overflow)
P3642R4: Carry-less product: std::clmul (Seen by SG6)
P3793R1: Better shifting (Seen by SG6)
P3772R1: std::simd overloads for bit permutations (Seen by SG6)