Tracking Issue for nonnull_provenance

[RalfJung]

Feature gate: #![feature(nonnull_provenance)]

This is a tracking issue for some provenance functions on NonNull that were missed in the initial strict provenance stabilization.

Public API

// core::ptr

impl<T> NonNull<T> {
    pub const fn without_provenance(addr: NonZero<usize>) -> Self;
    pub fn from_exposed_provenance(addr: NonZero<usize>) -> Self;
}
impl<T: ?Sized> NonNull<T> {
    pub fn expose_provenance(self) -> NonZero<usize>;
}

Steps / History

• ACP: Add expose_provenance and from_exposed_provenance on NonNull libs-team#518
• Implementation: add missing provenance APIs on NonNull #135242
• Final comment period (FCP)¹
• Stabilization PR

Unresolved Questions

• None yet.

Footnotes

1. https://std-dev-guide.rust-lang.org/feature-lifecycle/stabilization.html ↩

[scottmcm]

This without_provenance taking NonZero is beautiful, since it means that code (in Rc) that used to be NonNull::new_unchecked(ptr::without_provenance(MAX)) can now be safe 👍