Tracking Issue for `new_zeroed_alloc`

Feature gate: #![feature(new_zeroed_alloc)]

Split-out from https://github.com/rust-lang/rust/issues/63291 as a result of stabilizing most of its API! It's zeroed instead of uninit constructors, nothing too complicated!

Public API

It's new_zeroed and new_zeroed_slice on every major allocation type like Box, Rc, Arc.

impl<T> Box<T> { pub fn new_zeroed() -> Box<MaybeUninit<T>> {…} }
impl<T> Arc<T> { pub fn new_zeroed() -> Arc<MaybeUninit<T>> {…} }
impl<T> Rc<T> { pub fn new_zeroed() -> Rc<MaybeUninit<T>> {…} }

impl<[T]> Box<T> { pub fn new_zeroed_slice() -> Box<MaybeUninit<[T]>> {…} }
impl<[T]> Arc<T> { pub fn new_zeroed_slice() -> Arc<MaybeUninit<[T]>> {…} }
impl<[T]> Rc<T> { pub fn new_zeroed_slice() -> Rc<MaybeUninit<[T]>> {…} }

Steps / History

• Implementation: #...
  • added in https://github.com/rust-lang/rust/pull/66128
  • other API was added in https://github.com/rust-lang/rust/issues/63291
• Final comment period (FCP)^1
• Stabilization PR

Unresolved Questions

• idk lol

Start with implementation PR #66128 and the feature lifecycle stabilization guide linked in the issue. Review the listed new_zeroed and new_zeroed_slice APIs on Box, Arc, and Rc, then determine the remaining stabilization steps. Done means completing the final comment period and a stabilization PR.