rust/library/alloc/src/sync.rs, branch automation/bors/try

Rollup merge of #146886 - taiki-e:rc-inner-align, r=Mark-Simulacrum

2025-09-30T18:46:45+00:00

Add repr(align(2)) to RcInner and ArcInner `Rc` currently assumes that `RcInner` has at least 2-byte alignment, but on AVR, `usize` has 1-byte alignment (this is because the AVR has 1-byte register sizes, so having 2-byte alignment is generally useless), breaking this assumption. https://github.com/rust-lang/rust/blob/9f32ccf35fb877270bc44a86a126440f04d676d0/library/alloc/src/rc.rs#L3005-L3008 This PR adds `repr(align(2))` to force `RcInner` to always have at least 2-byte alignment. Note that `ArcInner` doesn't need `repr(align(2))` because atomic types have the alignment same as its size. This PR adds a comment about this.

Add repr(align(2)) to RcInner and ArcInner

2025-09-30T13:39:10+00:00

Update CURRENT_RUSTC_VERSION post-bump

2025-09-26T22:41:32+00:00

Remove unused #![feature(get_mut_unchecked)] in Rc and Arc examples

2025-09-22T13:15:25+00:00

Rollup merge of #144091 - thaliaarchi:stabilize-new-zeroed, r=Mark-Simulacrum

2025-09-21T04:42:33+00:00

Stabilize `new_zeroed_alloc` The corresponding `new_uninit` and `new_uninit_slice` functions were stabilized in rust-lang/rust#129401, but the zeroed counterparts were left for later out of a [desire](https://github.com/rust-lang/rust/issues/63291#issuecomment-2161039756) to stabilize only the minimal set. These functions are straightforward mirrors of the uninit functions and well-established. Since no blockers or design questions have surfaced in the past year, I think it's time to stabilize them. Tracking issue: rust-lang/rust#129396

remove deprecated Error::description in impls

2025-08-26T06:36:53+00:00

Stabilize `new_zeroed_alloc`

2025-07-20T03:25:35+00:00

Add `Default` impls for `Pin`ned `Box`, `Rc`, `Arc`

2025-07-15T21:41:31+00:00

Change `{Box,Arc,Rc,Weak}::into_raw` to only work with `A = Global`

2025-07-01T16:25:30+00:00

Also applies to `Vec::into_raw_parts`. The expectation is that you can round-trip these methods with `from_raw`, but this is only true when using the global allocator. With custom allocators you should instead be using `into_raw_with_allocator` and `from_raw_in`. The implementation of `Box::leak` is changed to use `Box::into_raw_with_allocator` and explicitly leak the allocator (which was already the existing behavior). This is because, for `leak` to be safe, the allocator must not free its underlying backing store. The `Allocator` trait only guarantees that allocated memory remains valid until the allocator is dropped.

Remove incorrect comments in `Weak`

2025-06-19T05:04:24+00:00

It is currently possible to create a dangling `Weak` to a DST by calling `Weak::new()` for a sized type, then doing an unsized coercion. Therefore, the comments are wrong. These comments were added in . As far as I can tell, the guarantee in the comment was only previously used in the `as_ptr` method. However, the current implementation of `as_ptr` no longer relies on this guarantee.