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Merged
merged 1 commit into from
Sep 21, 2025
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Stabilize new_zeroed_alloc #144091

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4 changes: 2 additions & 2 deletions compiler/rustc_index/src/bit_set.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -638,7 +638,7 @@ impl<T: Idx> ChunkedBitSet<T> {
};
#[cfg(not(feature = "nightly"))]
let mut words = {
// FIXME: unconditionally use `Rc::new_zeroed` once it is stable (#63291).
// FIXME: unconditionally use `Rc::new_zeroed` once it is stable (#129396).
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IIUC, this probably wants to replace the feature = nightly / not nightly with cfg on bootstrap, right? That the dead code will get automatically removed in the next bump.

We can probably do this in follow up though since there's not anything else missing from this PR and it's just a cleanup.

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I left that, to give some time for any crates relying on rustc_index to bump their MSRV. But I don't know our policy on that kind of thing.

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Ah, I guess that's true, that should probably wait until this makes it to stable. I don't think we should support more than a single (latest) stable release though.

let words = mem::MaybeUninit::<[Word; CHUNK_WORDS]>::zeroed();
// SAFETY: `words` can safely be all zeroes.
let words = unsafe { words.assume_init() };
Expand Down Expand Up @@ -704,7 +704,7 @@ impl<T: Idx> ChunkedBitSet<T> {
};
#[cfg(not(feature = "nightly"))]
let mut words = {
// FIXME: unconditionally use `Rc::new_zeroed` once it is stable (#63291).
// FIXME: unconditionally use `Rc::new_zeroed` once it is stable (#129396).
let words = mem::MaybeUninit::<[Word; CHUNK_WORDS]>::zeroed();
// SAFETY: `words` can safely be all zeroes.
let words = unsafe { words.assume_init() };
Expand Down
2 changes: 1 addition & 1 deletion compiler/rustc_index/src/lib.rs
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Original file line number Diff line number Diff line change
@@ -1,9 +1,9 @@
// tidy-alphabetical-start
#![cfg_attr(all(feature = "nightly", test), feature(stmt_expr_attributes))]
#![cfg_attr(bootstrap, feature(new_zeroed_alloc))]
#![cfg_attr(feature = "nightly", allow(internal_features))]
#![cfg_attr(feature = "nightly", feature(extend_one, step_trait, test))]
#![cfg_attr(feature = "nightly", feature(new_range_api))]
#![cfg_attr(feature = "nightly", feature(new_zeroed_alloc))]
// tidy-alphabetical-end

pub mod bit_set;
Expand Down
16 changes: 2 additions & 14 deletions library/alloc/src/boxed.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -290,8 +290,6 @@ impl<T> Box<T> {
/// # Examples
///
/// ```
/// #![feature(new_zeroed_alloc)]
///
/// let zero = Box::<u32>::new_zeroed();
/// let zero = unsafe { zero.assume_init() };
///
Expand All @@ -301,7 +299,7 @@ impl<T> Box<T> {
/// [zeroed]: mem::MaybeUninit::zeroed
#[cfg(not(no_global_oom_handling))]
#[inline]
#[unstable(feature = "new_zeroed_alloc", issue = "129396")]
#[stable(feature = "new_zeroed_alloc", since = "CURRENT_RUSTC_VERSION")]
#[must_use]
pub fn new_zeroed() -> Box<mem::MaybeUninit<T>> {
Self::new_zeroed_in(Global)
Expand Down Expand Up @@ -358,7 +356,6 @@ impl<T> Box<T> {
/// # Ok::<(), std::alloc::AllocError>(())
/// ```
#[unstable(feature = "allocator_api", issue = "32838")]
// #[unstable(feature = "new_uninit", issue = "63291")]
#[inline]
pub fn try_new_uninit() -> Result<Box<mem::MaybeUninit<T>>, AllocError> {
Box::try_new_uninit_in(Global)
Expand All @@ -384,7 +381,6 @@ impl<T> Box<T> {
///
/// [zeroed]: mem::MaybeUninit::zeroed
#[unstable(feature = "allocator_api", issue = "32838")]
// #[unstable(feature = "new_uninit", issue = "63291")]
#[inline]
pub fn try_new_zeroed() -> Result<Box<mem::MaybeUninit<T>>, AllocError> {
Box::try_new_zeroed_in(Global)
Expand Down Expand Up @@ -463,7 +459,6 @@ impl<T, A: Allocator> Box<T, A> {
#[unstable(feature = "allocator_api", issue = "32838")]
#[cfg(not(no_global_oom_handling))]
#[must_use]
// #[unstable(feature = "new_uninit", issue = "63291")]
pub fn new_uninit_in(alloc: A) -> Box<mem::MaybeUninit<T>, A>
where
A: Allocator,
Expand Down Expand Up @@ -496,7 +491,6 @@ impl<T, A: Allocator> Box<T, A> {
/// # Ok::<(), std::alloc::AllocError>(())
/// ```
#[unstable(feature = "allocator_api", issue = "32838")]
// #[unstable(feature = "new_uninit", issue = "63291")]
pub fn try_new_uninit_in(alloc: A) -> Result<Box<mem::MaybeUninit<T>, A>, AllocError>
where
A: Allocator,
Expand Down Expand Up @@ -532,7 +526,6 @@ impl<T, A: Allocator> Box<T, A> {
/// [zeroed]: mem::MaybeUninit::zeroed
#[unstable(feature = "allocator_api", issue = "32838")]
#[cfg(not(no_global_oom_handling))]
// #[unstable(feature = "new_uninit", issue = "63291")]
#[must_use]
pub fn new_zeroed_in(alloc: A) -> Box<mem::MaybeUninit<T>, A>
where
Expand Down Expand Up @@ -570,7 +563,6 @@ impl<T, A: Allocator> Box<T, A> {
///
/// [zeroed]: mem::MaybeUninit::zeroed
#[unstable(feature = "allocator_api", issue = "32838")]
// #[unstable(feature = "new_uninit", issue = "63291")]
pub fn try_new_zeroed_in(alloc: A) -> Result<Box<mem::MaybeUninit<T>, A>, AllocError>
where
A: Allocator,
Expand Down Expand Up @@ -660,8 +652,6 @@ impl<T> Box<[T]> {
/// # Examples
///
/// ```
/// #![feature(new_zeroed_alloc)]
///
/// let values = Box::<[u32]>::new_zeroed_slice(3);
/// let values = unsafe { values.assume_init() };
///
Expand All @@ -670,7 +660,7 @@ impl<T> Box<[T]> {
///
/// [zeroed]: mem::MaybeUninit::zeroed
#[cfg(not(no_global_oom_handling))]
#[unstable(feature = "new_zeroed_alloc", issue = "129396")]
#[stable(feature = "new_zeroed_alloc", since = "CURRENT_RUSTC_VERSION")]
#[must_use]
pub fn new_zeroed_slice(len: usize) -> Box<[mem::MaybeUninit<T>]> {
unsafe { RawVec::with_capacity_zeroed(len).into_box(len) }
Expand Down Expand Up @@ -785,7 +775,6 @@ impl<T, A: Allocator> Box<[T], A> {
/// ```
#[cfg(not(no_global_oom_handling))]
#[unstable(feature = "allocator_api", issue = "32838")]
// #[unstable(feature = "new_uninit", issue = "63291")]
#[must_use]
pub fn new_uninit_slice_in(len: usize, alloc: A) -> Box<[mem::MaybeUninit<T>], A> {
unsafe { RawVec::with_capacity_in(len, alloc).into_box(len) }
Expand Down Expand Up @@ -813,7 +802,6 @@ impl<T, A: Allocator> Box<[T], A> {
/// [zeroed]: mem::MaybeUninit::zeroed
#[cfg(not(no_global_oom_handling))]
#[unstable(feature = "allocator_api", issue = "32838")]
// #[unstable(feature = "new_uninit", issue = "63291")]
#[must_use]
pub fn new_zeroed_slice_in(len: usize, alloc: A) -> Box<[mem::MaybeUninit<T>], A> {
unsafe { RawVec::with_capacity_zeroed_in(len, alloc).into_box(len) }
Expand Down
16 changes: 2 additions & 14 deletions library/alloc/src/rc.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -515,8 +515,6 @@ impl<T> Rc<T> {
/// # Examples
///
/// ```
/// #![feature(new_zeroed_alloc)]
///
/// use std::rc::Rc;
///
/// let zero = Rc::<u32>::new_zeroed();
Expand All @@ -527,7 +525,7 @@ impl<T> Rc<T> {
///
/// [zeroed]: mem::MaybeUninit::zeroed
#[cfg(not(no_global_oom_handling))]
#[unstable(feature = "new_zeroed_alloc", issue = "129396")]
#[stable(feature = "new_zeroed_alloc", since = "CURRENT_RUSTC_VERSION")]
#[must_use]
pub fn new_zeroed() -> Rc<mem::MaybeUninit<T>> {
unsafe {
Expand Down Expand Up @@ -589,7 +587,6 @@ impl<T> Rc<T> {
/// # Ok::<(), std::alloc::AllocError>(())
/// ```
#[unstable(feature = "allocator_api", issue = "32838")]
// #[unstable(feature = "new_uninit", issue = "63291")]
pub fn try_new_uninit() -> Result<Rc<mem::MaybeUninit<T>>, AllocError> {
unsafe {
Ok(Rc::from_ptr(Rc::try_allocate_for_layout(
Expand Down Expand Up @@ -622,7 +619,6 @@ impl<T> Rc<T> {
///
/// [zeroed]: mem::MaybeUninit::zeroed
#[unstable(feature = "allocator_api", issue = "32838")]
//#[unstable(feature = "new_uninit", issue = "63291")]
pub fn try_new_zeroed() -> Result<Rc<mem::MaybeUninit<T>>, AllocError> {
unsafe {
Ok(Rc::from_ptr(Rc::try_allocate_for_layout(
Expand Down Expand Up @@ -690,7 +686,6 @@ impl<T, A: Allocator> Rc<T, A> {
/// ```
#[cfg(not(no_global_oom_handling))]
#[unstable(feature = "allocator_api", issue = "32838")]
// #[unstable(feature = "new_uninit", issue = "63291")]
#[inline]
pub fn new_uninit_in(alloc: A) -> Rc<mem::MaybeUninit<T>, A> {
unsafe {
Expand Down Expand Up @@ -728,7 +723,6 @@ impl<T, A: Allocator> Rc<T, A> {
/// [zeroed]: mem::MaybeUninit::zeroed
#[cfg(not(no_global_oom_handling))]
#[unstable(feature = "allocator_api", issue = "32838")]
// #[unstable(feature = "new_uninit", issue = "63291")]
#[inline]
pub fn new_zeroed_in(alloc: A) -> Rc<mem::MaybeUninit<T>, A> {
unsafe {
Expand Down Expand Up @@ -873,7 +867,6 @@ impl<T, A: Allocator> Rc<T, A> {
/// # Ok::<(), std::alloc::AllocError>(())
/// ```
#[unstable(feature = "allocator_api", issue = "32838")]
// #[unstable(feature = "new_uninit", issue = "63291")]
#[inline]
pub fn try_new_uninit_in(alloc: A) -> Result<Rc<mem::MaybeUninit<T>, A>, AllocError> {
unsafe {
Expand Down Expand Up @@ -912,7 +905,6 @@ impl<T, A: Allocator> Rc<T, A> {
///
/// [zeroed]: mem::MaybeUninit::zeroed
#[unstable(feature = "allocator_api", issue = "32838")]
//#[unstable(feature = "new_uninit", issue = "63291")]
#[inline]
pub fn try_new_zeroed_in(alloc: A) -> Result<Rc<mem::MaybeUninit<T>, A>, AllocError> {
unsafe {
Expand Down Expand Up @@ -1054,8 +1046,6 @@ impl<T> Rc<[T]> {
/// # Examples
///
/// ```
/// #![feature(new_zeroed_alloc)]
///
/// use std::rc::Rc;
///
/// let values = Rc::<[u32]>::new_zeroed_slice(3);
Expand All @@ -1066,7 +1056,7 @@ impl<T> Rc<[T]> {
///
/// [zeroed]: mem::MaybeUninit::zeroed
#[cfg(not(no_global_oom_handling))]
#[unstable(feature = "new_zeroed_alloc", issue = "129396")]
#[stable(feature = "new_zeroed_alloc", since = "CURRENT_RUSTC_VERSION")]
#[must_use]
pub fn new_zeroed_slice(len: usize) -> Rc<[mem::MaybeUninit<T>]> {
unsafe {
Expand Down Expand Up @@ -1129,7 +1119,6 @@ impl<T, A: Allocator> Rc<[T], A> {
/// ```
#[cfg(not(no_global_oom_handling))]
#[unstable(feature = "allocator_api", issue = "32838")]
// #[unstable(feature = "new_uninit", issue = "63291")]
#[inline]
pub fn new_uninit_slice_in(len: usize, alloc: A) -> Rc<[mem::MaybeUninit<T>], A> {
unsafe { Rc::from_ptr_in(Rc::allocate_for_slice_in(len, &alloc), alloc) }
Expand Down Expand Up @@ -1158,7 +1147,6 @@ impl<T, A: Allocator> Rc<[T], A> {
/// [zeroed]: mem::MaybeUninit::zeroed
#[cfg(not(no_global_oom_handling))]
#[unstable(feature = "allocator_api", issue = "32838")]
// #[unstable(feature = "new_uninit", issue = "63291")]
#[inline]
pub fn new_zeroed_slice_in(len: usize, alloc: A) -> Rc<[mem::MaybeUninit<T>], A> {
unsafe {
Expand Down
14 changes: 2 additions & 12 deletions library/alloc/src/sync.rs
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Expand Up @@ -516,8 +516,6 @@ impl<T> Arc<T> {
/// # Examples
///
/// ```
/// #![feature(new_zeroed_alloc)]
///
/// use std::sync::Arc;
///
/// let zero = Arc::<u32>::new_zeroed();
Expand All @@ -529,7 +527,7 @@ impl<T> Arc<T> {
/// [zeroed]: mem::MaybeUninit::zeroed
#[cfg(not(no_global_oom_handling))]
#[inline]
#[unstable(feature = "new_zeroed_alloc", issue = "129396")]
#[stable(feature = "new_zeroed_alloc", since = "CURRENT_RUSTC_VERSION")]
#[must_use]
pub fn new_zeroed() -> Arc<mem::MaybeUninit<T>> {
unsafe {
Expand Down Expand Up @@ -603,7 +601,6 @@ impl<T> Arc<T> {
/// # Ok::<(), std::alloc::AllocError>(())
/// ```
#[unstable(feature = "allocator_api", issue = "32838")]
// #[unstable(feature = "new_uninit", issue = "63291")]
pub fn try_new_uninit() -> Result<Arc<mem::MaybeUninit<T>>, AllocError> {
unsafe {
Ok(Arc::from_ptr(Arc::try_allocate_for_layout(
Expand Down Expand Up @@ -636,7 +633,6 @@ impl<T> Arc<T> {
///
/// [zeroed]: mem::MaybeUninit::zeroed
#[unstable(feature = "allocator_api", issue = "32838")]
// #[unstable(feature = "new_uninit", issue = "63291")]
pub fn try_new_zeroed() -> Result<Arc<mem::MaybeUninit<T>>, AllocError> {
unsafe {
Ok(Arc::from_ptr(Arc::try_allocate_for_layout(
Expand Down Expand Up @@ -703,7 +699,6 @@ impl<T, A: Allocator> Arc<T, A> {
/// ```
#[cfg(not(no_global_oom_handling))]
#[unstable(feature = "allocator_api", issue = "32838")]
// #[unstable(feature = "new_uninit", issue = "63291")]
#[inline]
pub fn new_uninit_in(alloc: A) -> Arc<mem::MaybeUninit<T>, A> {
unsafe {
Expand Down Expand Up @@ -741,7 +736,6 @@ impl<T, A: Allocator> Arc<T, A> {
/// [zeroed]: mem::MaybeUninit::zeroed
#[cfg(not(no_global_oom_handling))]
#[unstable(feature = "allocator_api", issue = "32838")]
// #[unstable(feature = "new_uninit", issue = "63291")]
#[inline]
pub fn new_zeroed_in(alloc: A) -> Arc<mem::MaybeUninit<T>, A> {
unsafe {
Expand Down Expand Up @@ -927,7 +921,6 @@ impl<T, A: Allocator> Arc<T, A> {
/// # Ok::<(), std::alloc::AllocError>(())
/// ```
#[unstable(feature = "allocator_api", issue = "32838")]
// #[unstable(feature = "new_uninit", issue = "63291")]
#[inline]
pub fn try_new_uninit_in(alloc: A) -> Result<Arc<mem::MaybeUninit<T>, A>, AllocError> {
unsafe {
Expand Down Expand Up @@ -966,7 +959,6 @@ impl<T, A: Allocator> Arc<T, A> {
///
/// [zeroed]: mem::MaybeUninit::zeroed
#[unstable(feature = "allocator_api", issue = "32838")]
// #[unstable(feature = "new_uninit", issue = "63291")]
#[inline]
pub fn try_new_zeroed_in(alloc: A) -> Result<Arc<mem::MaybeUninit<T>, A>, AllocError> {
unsafe {
Expand Down Expand Up @@ -1197,8 +1189,6 @@ impl<T> Arc<[T]> {
/// # Examples
///
/// ```
/// #![feature(new_zeroed_alloc)]
///
/// use std::sync::Arc;
///
/// let values = Arc::<[u32]>::new_zeroed_slice(3);
Expand All @@ -1210,7 +1200,7 @@ impl<T> Arc<[T]> {
/// [zeroed]: mem::MaybeUninit::zeroed
#[cfg(not(no_global_oom_handling))]
#[inline]
#[unstable(feature = "new_zeroed_alloc", issue = "129396")]
#[stable(feature = "new_zeroed_alloc", since = "CURRENT_RUSTC_VERSION")]
#[must_use]
pub fn new_zeroed_slice(len: usize) -> Arc<[mem::MaybeUninit<T>]> {
unsafe {
Expand Down
1 change: 0 additions & 1 deletion library/std/src/lib.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -376,7 +376,6 @@
#![feature(allocator_api)]
#![feature(get_mut_unchecked)]
#![feature(map_try_insert)]
#![feature(new_zeroed_alloc)]
#![feature(slice_concat_trait)]
#![feature(thin_box)]
#![feature(try_reserve_kind)]
Expand Down
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