Repository: rust
Issue: Tracking Issue for pointer_is_aligned_to
Labels: T-libs-api,C-tracking-issue

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~~Feature gate: `#![feature(pointer_is_aligned)]`~~
Feature gate: `#![feature(pointer_is_aligned_to)]`

This is a tracking issue for ~~`ptr.is_aligned()` and~~ `ptr.is_aligned_to(alignment)`.

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### Public API

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```rust
impl *const T {
    // feature gate `pointer_is_aligned` was stabilized
    // pub fn is_aligned(self) -> bool where T: Sized;
    // feature gate `pointer_is_aligned_to`
    pub fn is_aligned_to(self, align: usize) -> bool;
}
// ... and the same for` *mut T`

impl <T: ?Sized> NonNull<T> {
    pub const fn is_aligned_to(self, align: usize) -> bool;
}
```

### Steps / History

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`pointer_is_aligned`:

- [x] Implementation: #95643
- [x] Final comment period (FCP): https://github.com/rust-lang/rust/pull/121948#issuecomment-2000619990
- [x] Stabilization PR: https://github.com/rust-lang/rust/pull/121948

`pointer_is_aligned_to`:
- [x] Implementation: #95643 and https://github.com/rust-lang/rust/pull/121948
- [x] Move the `NonNull` method to this gate https://github.com/rust-lang/rust/pull/124498
- [ ] Final comment period (FCP)
- [ ] Stabilization PR
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### Unresolved Questions

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- Should is_aligned_to require a power of two or should it be more flexible? (currently panics)