Issue 4518: `simd::cat` return type requires inefficient ABI tag change/conversion

Title: `simd::cat` return type requires inefficient ABI tag change/conversion
Status: new
Section: [simd.syn][simd.creation]
Submitter: Matthias Kretz

Created on 2025-11-25.00:00:00 last changed 2 months ago

Messages

Date: 2025-11-25.00:00:00

The return type of `simd::cat` is defined using deduce-abi-t rather than `resize_t`. This can lead to:

basic_vec<T, Abi> x = […]
auto [...vs] = simd::chunk<2>(x);
auto y = simd::cat(vs...);
static_assert(is_same_v<decltype(x), decltype(y)>); // can fail

History
Date	User	Action	Args
2025-11-25 00:00:00	admin	create