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rust: alloc: implement kernel Vec type
`Vec` provides a contiguous growable array type with contents allocated with the kernel's allocators (e.g. `Kmalloc`, `Vmalloc` or `KVmalloc`). In contrast to Rust's stdlib `Vec` type, the kernel `Vec` type considers the kernel's GFP flags for all appropriate functions, always reports allocation failures through `Result<_, AllocError>` and remains independent from unstable features. [ This patch starts using a new unstable feature, `inline_const`, but it was stabilized in Rust 1.79.0, i.e. the next version after the minimum one, thus it will not be an issue. - Miguel ] Reviewed-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Gary Guo <gary@garyguo.net> Signed-off-by: Danilo Krummrich <dakr@kernel.org> Link: https://lore.kernel.org/r/20241004154149.93856-17-dakr@kernel.org [ Cleaned `rustdoc` unescaped backtick warning, added a couple more backticks elsewhere, fixed typos, sorted `feature`s, rewrapped documentation lines. - Miguel ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This commit is contained in:
Danilo Krummrich
Miguel Ojeda
parent
9e7bbfa182
commit
2aac4cd7da
4 changed files with 656 additions and 1 deletions
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@ -5,6 +5,7 @@
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#[cfg(not(any(test, testlib)))]
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pub mod allocator;
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pub mod kbox;
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pub mod kvec;
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pub mod layout;
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pub mod vec_ext;
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@ -19,6 +20,11 @@
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pub use self::kbox::KVBox;
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pub use self::kbox::VBox;
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pub use self::kvec::KVVec;
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pub use self::kvec::KVec;
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pub use self::kvec::VVec;
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pub use self::kvec::Vec;
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/// Indicates an allocation error.
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#[derive(Copy, Clone, PartialEq, Eq, Debug)]
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pub struct AllocError;
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648
rust/kernel/alloc/kvec.rs
Normal file
648
rust/kernel/alloc/kvec.rs
Normal file
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@ -0,0 +1,648 @@
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// SPDX-License-Identifier: GPL-2.0
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//! Implementation of [`Vec`].
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use super::{
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allocator::{KVmalloc, Kmalloc, Vmalloc},
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layout::ArrayLayout,
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AllocError, Allocator, Box, Flags,
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};
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use core::{
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fmt,
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marker::PhantomData,
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mem::{ManuallyDrop, MaybeUninit},
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ops::Deref,
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ops::DerefMut,
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ops::Index,
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ops::IndexMut,
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ptr,
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ptr::NonNull,
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slice,
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slice::SliceIndex,
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};
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/// Create a [`KVec`] containing the arguments.
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///
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/// New memory is allocated with `GFP_KERNEL`.
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///
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/// # Examples
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///
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/// ```
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/// let mut v = kernel::kvec![];
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/// v.push(1, GFP_KERNEL)?;
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/// assert_eq!(v, [1]);
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///
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/// let mut v = kernel::kvec![1; 3]?;
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/// v.push(4, GFP_KERNEL)?;
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/// assert_eq!(v, [1, 1, 1, 4]);
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///
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/// let mut v = kernel::kvec![1, 2, 3]?;
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/// v.push(4, GFP_KERNEL)?;
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/// assert_eq!(v, [1, 2, 3, 4]);
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///
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/// # Ok::<(), Error>(())
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/// ```
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#[macro_export]
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macro_rules! kvec {
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() => (
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$crate::alloc::KVec::new()
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);
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($elem:expr; $n:expr) => (
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$crate::alloc::KVec::from_elem($elem, $n, GFP_KERNEL)
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);
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($($x:expr),+ $(,)?) => (
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match $crate::alloc::KBox::new_uninit(GFP_KERNEL) {
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Ok(b) => Ok($crate::alloc::KVec::from($crate::alloc::KBox::write(b, [$($x),+]))),
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Err(e) => Err(e),
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}
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);
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}
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/// The kernel's [`Vec`] type.
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///
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/// A contiguous growable array type with contents allocated with the kernel's allocators (e.g.
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/// [`Kmalloc`], [`Vmalloc`] or [`KVmalloc`]), written `Vec<T, A>`.
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///
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/// For non-zero-sized values, a [`Vec`] will use the given allocator `A` for its allocation. For
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/// the most common allocators the type aliases [`KVec`], [`VVec`] and [`KVVec`] exist.
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///
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/// For zero-sized types the [`Vec`]'s pointer must be `dangling_mut::<T>`; no memory is allocated.
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///
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/// Generally, [`Vec`] consists of a pointer that represents the vector's backing buffer, the
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/// capacity of the vector (the number of elements that currently fit into the vector), its length
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/// (the number of elements that are currently stored in the vector) and the `Allocator` type used
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/// to allocate (and free) the backing buffer.
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///
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/// A [`Vec`] can be deconstructed into and (re-)constructed from its previously named raw parts
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/// and manually modified.
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///
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/// [`Vec`]'s backing buffer gets, if required, automatically increased (re-allocated) when elements
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/// are added to the vector.
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///
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/// # Invariants
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///
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/// - `self.ptr` is always properly aligned and either points to memory allocated with `A` or, for
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/// zero-sized types, is a dangling, well aligned pointer.
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///
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/// - `self.len` always represents the exact number of elements stored in the vector.
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///
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/// - `self.layout` represents the absolute number of elements that can be stored within the vector
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/// without re-allocation. For ZSTs `self.layout`'s capacity is zero. However, it is legal for the
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/// backing buffer to be larger than `layout`.
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///
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/// - The `Allocator` type `A` of the vector is the exact same `Allocator` type the backing buffer
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/// was allocated with (and must be freed with).
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pub struct Vec<T, A: Allocator> {
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ptr: NonNull<T>,
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/// Represents the actual buffer size as `cap` times `size_of::<T>` bytes.
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///
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/// Note: This isn't quite the same as `Self::capacity`, which in contrast returns the number of
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/// elements we can still store without reallocating.
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layout: ArrayLayout<T>,
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len: usize,
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_p: PhantomData<A>,
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}
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/// Type alias for [`Vec`] with a [`Kmalloc`] allocator.
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///
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/// # Examples
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///
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/// ```
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/// let mut v = KVec::new();
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/// v.push(1, GFP_KERNEL)?;
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/// assert_eq!(&v, &[1]);
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///
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/// # Ok::<(), Error>(())
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/// ```
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pub type KVec<T> = Vec<T, Kmalloc>;
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/// Type alias for [`Vec`] with a [`Vmalloc`] allocator.
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///
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/// # Examples
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///
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/// ```
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/// let mut v = VVec::new();
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/// v.push(1, GFP_KERNEL)?;
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/// assert_eq!(&v, &[1]);
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///
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/// # Ok::<(), Error>(())
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/// ```
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pub type VVec<T> = Vec<T, Vmalloc>;
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/// Type alias for [`Vec`] with a [`KVmalloc`] allocator.
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///
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/// # Examples
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///
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/// ```
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/// let mut v = KVVec::new();
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/// v.push(1, GFP_KERNEL)?;
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/// assert_eq!(&v, &[1]);
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///
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/// # Ok::<(), Error>(())
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/// ```
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pub type KVVec<T> = Vec<T, KVmalloc>;
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// SAFETY: `Vec` is `Send` if `T` is `Send` because `Vec` owns its elements.
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unsafe impl<T, A> Send for Vec<T, A>
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where
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T: Send,
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A: Allocator,
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{
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}
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// SAFETY: `Vec` is `Sync` if `T` is `Sync` because `Vec` owns its elements.
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unsafe impl<T, A> Sync for Vec<T, A>
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where
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T: Sync,
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A: Allocator,
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{
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}
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impl<T, A> Vec<T, A>
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where
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A: Allocator,
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{
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#[inline]
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const fn is_zst() -> bool {
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core::mem::size_of::<T>() == 0
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}
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/// Returns the number of elements that can be stored within the vector without allocating
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/// additional memory.
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pub fn capacity(&self) -> usize {
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if const { Self::is_zst() } {
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usize::MAX
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} else {
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self.layout.len()
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}
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}
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/// Returns the number of elements stored within the vector.
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#[inline]
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pub fn len(&self) -> usize {
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self.len
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}
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/// Forcefully sets `self.len` to `new_len`.
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///
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/// # Safety
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///
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/// - `new_len` must be less than or equal to [`Self::capacity`].
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/// - If `new_len` is greater than `self.len`, all elements within the interval
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/// [`self.len`,`new_len`) must be initialized.
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#[inline]
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pub unsafe fn set_len(&mut self, new_len: usize) {
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debug_assert!(new_len <= self.capacity());
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self.len = new_len;
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}
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/// Returns a slice of the entire vector.
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#[inline]
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pub fn as_slice(&self) -> &[T] {
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self
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}
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/// Returns a mutable slice of the entire vector.
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#[inline]
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pub fn as_mut_slice(&mut self) -> &mut [T] {
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self
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}
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/// Returns a mutable raw pointer to the vector's backing buffer, or, if `T` is a ZST, a
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/// dangling raw pointer.
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#[inline]
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pub fn as_mut_ptr(&mut self) -> *mut T {
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self.ptr.as_ptr()
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}
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/// Returns a raw pointer to the vector's backing buffer, or, if `T` is a ZST, a dangling raw
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/// pointer.
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#[inline]
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pub fn as_ptr(&self) -> *const T {
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self.ptr.as_ptr()
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}
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/// Returns `true` if the vector contains no elements, `false` otherwise.
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///
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/// # Examples
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///
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/// ```
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/// let mut v = KVec::new();
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/// assert!(v.is_empty());
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///
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/// v.push(1, GFP_KERNEL);
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/// assert!(!v.is_empty());
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/// ```
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#[inline]
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pub fn is_empty(&self) -> bool {
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self.len() == 0
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}
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/// Creates a new, empty `Vec<T, A>`.
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///
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/// This method does not allocate by itself.
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#[inline]
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pub const fn new() -> Self {
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// INVARIANT: Since this is a new, empty `Vec` with no backing memory yet,
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// - `ptr` is a properly aligned dangling pointer for type `T`,
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// - `layout` is an empty `ArrayLayout` (zero capacity)
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// - `len` is zero, since no elements can be or have been stored,
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// - `A` is always valid.
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Self {
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ptr: NonNull::dangling(),
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layout: ArrayLayout::empty(),
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len: 0,
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_p: PhantomData::<A>,
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}
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}
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/// Returns a slice of `MaybeUninit<T>` for the remaining spare capacity of the vector.
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pub fn spare_capacity_mut(&mut self) -> &mut [MaybeUninit<T>] {
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// SAFETY:
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// - `self.len` is smaller than `self.capacity` and hence, the resulting pointer is
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// guaranteed to be part of the same allocated object.
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// - `self.len` can not overflow `isize`.
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let ptr = unsafe { self.as_mut_ptr().add(self.len) } as *mut MaybeUninit<T>;
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// SAFETY: The memory between `self.len` and `self.capacity` is guaranteed to be allocated
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// and valid, but uninitialized.
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unsafe { slice::from_raw_parts_mut(ptr, self.capacity() - self.len) }
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}
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/// Appends an element to the back of the [`Vec`] instance.
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///
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/// # Examples
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///
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/// ```
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/// let mut v = KVec::new();
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/// v.push(1, GFP_KERNEL)?;
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/// assert_eq!(&v, &[1]);
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///
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/// v.push(2, GFP_KERNEL)?;
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/// assert_eq!(&v, &[1, 2]);
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/// # Ok::<(), Error>(())
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/// ```
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pub fn push(&mut self, v: T, flags: Flags) -> Result<(), AllocError> {
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self.reserve(1, flags)?;
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// SAFETY:
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// - `self.len` is smaller than `self.capacity` and hence, the resulting pointer is
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// guaranteed to be part of the same allocated object.
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// - `self.len` can not overflow `isize`.
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let ptr = unsafe { self.as_mut_ptr().add(self.len) };
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// SAFETY:
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// - `ptr` is properly aligned and valid for writes.
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unsafe { core::ptr::write(ptr, v) };
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// SAFETY: We just initialised the first spare entry, so it is safe to increase the length
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// by 1. We also know that the new length is <= capacity because of the previous call to
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// `reserve` above.
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unsafe { self.set_len(self.len() + 1) };
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Ok(())
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}
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/// Creates a new [`Vec`] instance with at least the given capacity.
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///
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/// # Examples
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///
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/// ```
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/// let v = KVec::<u32>::with_capacity(20, GFP_KERNEL)?;
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///
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/// assert!(v.capacity() >= 20);
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/// # Ok::<(), Error>(())
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/// ```
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pub fn with_capacity(capacity: usize, flags: Flags) -> Result<Self, AllocError> {
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let mut v = Vec::new();
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v.reserve(capacity, flags)?;
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Ok(v)
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}
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/// Creates a `Vec<T, A>` from a pointer, a length and a capacity using the allocator `A`.
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///
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/// # Examples
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///
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/// ```
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/// let mut v = kernel::kvec![1, 2, 3]?;
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/// v.reserve(1, GFP_KERNEL)?;
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///
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/// let (mut ptr, mut len, cap) = v.into_raw_parts();
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///
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/// // SAFETY: We've just reserved memory for another element.
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/// unsafe { ptr.add(len).write(4) };
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/// len += 1;
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///
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/// // SAFETY: We only wrote an additional element at the end of the `KVec`'s buffer and
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/// // correspondingly increased the length of the `KVec` by one. Otherwise, we construct it
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/// // from the exact same raw parts.
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/// let v = unsafe { KVec::from_raw_parts(ptr, len, cap) };
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///
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/// assert_eq!(v, [1, 2, 3, 4]);
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///
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/// # Ok::<(), Error>(())
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/// ```
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///
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/// # Safety
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///
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/// If `T` is a ZST:
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///
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/// - `ptr` must be a dangling, well aligned pointer.
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///
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/// Otherwise:
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///
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/// - `ptr` must have been allocated with the allocator `A`.
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/// - `ptr` must satisfy or exceed the alignment requirements of `T`.
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/// - `ptr` must point to memory with a size of at least `size_of::<T>() * capacity` bytes.
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/// - The allocated size in bytes must not be larger than `isize::MAX`.
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/// - `length` must be less than or equal to `capacity`.
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/// - The first `length` elements must be initialized values of type `T`.
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///
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/// It is also valid to create an empty `Vec` passing a dangling pointer for `ptr` and zero for
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/// `cap` and `len`.
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pub unsafe fn from_raw_parts(ptr: *mut T, length: usize, capacity: usize) -> Self {
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let layout = if Self::is_zst() {
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ArrayLayout::empty()
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} else {
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// SAFETY: By the safety requirements of this function, `capacity * size_of::<T>()` is
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// smaller than `isize::MAX`.
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unsafe { ArrayLayout::new_unchecked(capacity) }
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};
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// INVARIANT: For ZSTs, we store an empty `ArrayLayout`, all other type invariants are
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// covered by the safety requirements of this function.
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Self {
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// SAFETY: By the safety requirements, `ptr` is either dangling or pointing to a valid
|
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// memory allocation, allocated with `A`.
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ptr: unsafe { NonNull::new_unchecked(ptr) },
|
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layout,
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len: length,
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_p: PhantomData::<A>,
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}
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}
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/// Consumes the `Vec<T, A>` and returns its raw components `pointer`, `length` and `capacity`.
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///
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/// This will not run the destructor of the contained elements and for non-ZSTs the allocation
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/// will stay alive indefinitely. Use [`Vec::from_raw_parts`] to recover the [`Vec`], drop the
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/// elements and free the allocation, if any.
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pub fn into_raw_parts(self) -> (*mut T, usize, usize) {
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let mut me = ManuallyDrop::new(self);
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let len = me.len();
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let capacity = me.capacity();
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let ptr = me.as_mut_ptr();
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(ptr, len, capacity)
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}
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|
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/// Ensures that the capacity exceeds the length by at least `additional` elements.
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///
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/// # Examples
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///
|
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/// ```
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/// let mut v = KVec::new();
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/// v.push(1, GFP_KERNEL)?;
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///
|
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/// v.reserve(10, GFP_KERNEL)?;
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/// let cap = v.capacity();
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/// assert!(cap >= 10);
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///
|
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/// v.reserve(10, GFP_KERNEL)?;
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/// let new_cap = v.capacity();
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/// assert_eq!(new_cap, cap);
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///
|
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/// # Ok::<(), Error>(())
|
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/// ```
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pub fn reserve(&mut self, additional: usize, flags: Flags) -> Result<(), AllocError> {
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let len = self.len();
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let cap = self.capacity();
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|
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if cap - len >= additional {
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return Ok(());
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}
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|
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if Self::is_zst() {
|
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// The capacity is already `usize::MAX` for ZSTs, we can't go higher.
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return Err(AllocError);
|
||||
}
|
||||
|
||||
// We know that `cap <= isize::MAX` because of the type invariants of `Self`. So the
|
||||
// multiplication by two won't overflow.
|
||||
let new_cap = core::cmp::max(cap * 2, len.checked_add(additional).ok_or(AllocError)?);
|
||||
let layout = ArrayLayout::new(new_cap).map_err(|_| AllocError)?;
|
||||
|
||||
// SAFETY:
|
||||
// - `ptr` is valid because it's either `None` or comes from a previous call to
|
||||
// `A::realloc`.
|
||||
// - `self.layout` matches the `ArrayLayout` of the preceding allocation.
|
||||
let ptr = unsafe {
|
||||
A::realloc(
|
||||
Some(self.ptr.cast()),
|
||||
layout.into(),
|
||||
self.layout.into(),
|
||||
flags,
|
||||
)?
|
||||
};
|
||||
|
||||
// INVARIANT:
|
||||
// - `layout` is some `ArrayLayout::<T>`,
|
||||
// - `ptr` has been created by `A::realloc` from `layout`.
|
||||
self.ptr = ptr.cast();
|
||||
self.layout = layout;
|
||||
|
||||
Ok(())
|
||||
}
|
||||
}
|
||||
|
||||
impl<T: Clone, A: Allocator> Vec<T, A> {
|
||||
/// Extend the vector by `n` clones of `value`.
|
||||
pub fn extend_with(&mut self, n: usize, value: T, flags: Flags) -> Result<(), AllocError> {
|
||||
if n == 0 {
|
||||
return Ok(());
|
||||
}
|
||||
|
||||
self.reserve(n, flags)?;
|
||||
|
||||
let spare = self.spare_capacity_mut();
|
||||
|
||||
for item in spare.iter_mut().take(n - 1) {
|
||||
item.write(value.clone());
|
||||
}
|
||||
|
||||
// We can write the last element directly without cloning needlessly.
|
||||
spare[n - 1].write(value);
|
||||
|
||||
// SAFETY:
|
||||
// - `self.len() + n < self.capacity()` due to the call to reserve above,
|
||||
// - the loop and the line above initialized the next `n` elements.
|
||||
unsafe { self.set_len(self.len() + n) };
|
||||
|
||||
Ok(())
|
||||
}
|
||||
|
||||
/// Pushes clones of the elements of slice into the [`Vec`] instance.
|
||||
///
|
||||
/// # Examples
|
||||
///
|
||||
/// ```
|
||||
/// let mut v = KVec::new();
|
||||
/// v.push(1, GFP_KERNEL)?;
|
||||
///
|
||||
/// v.extend_from_slice(&[20, 30, 40], GFP_KERNEL)?;
|
||||
/// assert_eq!(&v, &[1, 20, 30, 40]);
|
||||
///
|
||||
/// v.extend_from_slice(&[50, 60], GFP_KERNEL)?;
|
||||
/// assert_eq!(&v, &[1, 20, 30, 40, 50, 60]);
|
||||
/// # Ok::<(), Error>(())
|
||||
/// ```
|
||||
pub fn extend_from_slice(&mut self, other: &[T], flags: Flags) -> Result<(), AllocError> {
|
||||
self.reserve(other.len(), flags)?;
|
||||
for (slot, item) in core::iter::zip(self.spare_capacity_mut(), other) {
|
||||
slot.write(item.clone());
|
||||
}
|
||||
|
||||
// SAFETY:
|
||||
// - `other.len()` spare entries have just been initialized, so it is safe to increase
|
||||
// the length by the same number.
|
||||
// - `self.len() + other.len() <= self.capacity()` is guaranteed by the preceding `reserve`
|
||||
// call.
|
||||
unsafe { self.set_len(self.len() + other.len()) };
|
||||
Ok(())
|
||||
}
|
||||
|
||||
/// Create a new `Vec<T, A>` and extend it by `n` clones of `value`.
|
||||
pub fn from_elem(value: T, n: usize, flags: Flags) -> Result<Self, AllocError> {
|
||||
let mut v = Self::with_capacity(n, flags)?;
|
||||
|
||||
v.extend_with(n, value, flags)?;
|
||||
|
||||
Ok(v)
|
||||
}
|
||||
}
|
||||
|
||||
impl<T, A> Drop for Vec<T, A>
|
||||
where
|
||||
A: Allocator,
|
||||
{
|
||||
fn drop(&mut self) {
|
||||
// SAFETY: `self.as_mut_ptr` is guaranteed to be valid by the type invariant.
|
||||
unsafe {
|
||||
ptr::drop_in_place(core::ptr::slice_from_raw_parts_mut(
|
||||
self.as_mut_ptr(),
|
||||
self.len,
|
||||
))
|
||||
};
|
||||
|
||||
// SAFETY:
|
||||
// - `self.ptr` was previously allocated with `A`.
|
||||
// - `self.layout` matches the `ArrayLayout` of the preceding allocation.
|
||||
unsafe { A::free(self.ptr.cast(), self.layout.into()) };
|
||||
}
|
||||
}
|
||||
|
||||
impl<T, A, const N: usize> From<Box<[T; N], A>> for Vec<T, A>
|
||||
where
|
||||
A: Allocator,
|
||||
{
|
||||
fn from(b: Box<[T; N], A>) -> Vec<T, A> {
|
||||
let len = b.len();
|
||||
let ptr = Box::into_raw(b);
|
||||
|
||||
// SAFETY:
|
||||
// - `b` has been allocated with `A`,
|
||||
// - `ptr` fulfills the alignment requirements for `T`,
|
||||
// - `ptr` points to memory with at least a size of `size_of::<T>() * len`,
|
||||
// - all elements within `b` are initialized values of `T`,
|
||||
// - `len` does not exceed `isize::MAX`.
|
||||
unsafe { Vec::from_raw_parts(ptr as _, len, len) }
|
||||
}
|
||||
}
|
||||
|
||||
impl<T> Default for KVec<T> {
|
||||
#[inline]
|
||||
fn default() -> Self {
|
||||
Self::new()
|
||||
}
|
||||
}
|
||||
|
||||
impl<T: fmt::Debug, A: Allocator> fmt::Debug for Vec<T, A> {
|
||||
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
|
||||
fmt::Debug::fmt(&**self, f)
|
||||
}
|
||||
}
|
||||
|
||||
impl<T, A> Deref for Vec<T, A>
|
||||
where
|
||||
A: Allocator,
|
||||
{
|
||||
type Target = [T];
|
||||
|
||||
#[inline]
|
||||
fn deref(&self) -> &[T] {
|
||||
// SAFETY: The memory behind `self.as_ptr()` is guaranteed to contain `self.len`
|
||||
// initialized elements of type `T`.
|
||||
unsafe { slice::from_raw_parts(self.as_ptr(), self.len) }
|
||||
}
|
||||
}
|
||||
|
||||
impl<T, A> DerefMut for Vec<T, A>
|
||||
where
|
||||
A: Allocator,
|
||||
{
|
||||
#[inline]
|
||||
fn deref_mut(&mut self) -> &mut [T] {
|
||||
// SAFETY: The memory behind `self.as_ptr()` is guaranteed to contain `self.len`
|
||||
// initialized elements of type `T`.
|
||||
unsafe { slice::from_raw_parts_mut(self.as_mut_ptr(), self.len) }
|
||||
}
|
||||
}
|
||||
|
||||
impl<T: Eq, A> Eq for Vec<T, A> where A: Allocator {}
|
||||
|
||||
impl<T, I: SliceIndex<[T]>, A> Index<I> for Vec<T, A>
|
||||
where
|
||||
A: Allocator,
|
||||
{
|
||||
type Output = I::Output;
|
||||
|
||||
#[inline]
|
||||
fn index(&self, index: I) -> &Self::Output {
|
||||
Index::index(&**self, index)
|
||||
}
|
||||
}
|
||||
|
||||
impl<T, I: SliceIndex<[T]>, A> IndexMut<I> for Vec<T, A>
|
||||
where
|
||||
A: Allocator,
|
||||
{
|
||||
#[inline]
|
||||
fn index_mut(&mut self, index: I) -> &mut Self::Output {
|
||||
IndexMut::index_mut(&mut **self, index)
|
||||
}
|
||||
}
|
||||
|
||||
macro_rules! impl_slice_eq {
|
||||
($([$($vars:tt)*] $lhs:ty, $rhs:ty,)*) => {
|
||||
$(
|
||||
impl<T, U, $($vars)*> PartialEq<$rhs> for $lhs
|
||||
where
|
||||
T: PartialEq<U>,
|
||||
{
|
||||
#[inline]
|
||||
fn eq(&self, other: &$rhs) -> bool { self[..] == other[..] }
|
||||
}
|
||||
)*
|
||||
}
|
||||
}
|
||||
|
||||
impl_slice_eq! {
|
||||
[A1: Allocator, A2: Allocator] Vec<T, A1>, Vec<U, A2>,
|
||||
[A: Allocator] Vec<T, A>, &[U],
|
||||
[A: Allocator] Vec<T, A>, &mut [U],
|
||||
[A: Allocator] &[T], Vec<U, A>,
|
||||
[A: Allocator] &mut [T], Vec<U, A>,
|
||||
[A: Allocator] Vec<T, A>, [U],
|
||||
[A: Allocator] [T], Vec<U, A>,
|
||||
[A: Allocator, const N: usize] Vec<T, A>, [U; N],
|
||||
[A: Allocator, const N: usize] Vec<T, A>, &[U; N],
|
||||
}
|
||||
|
|
@ -15,6 +15,7 @@
|
|||
#![feature(arbitrary_self_types)]
|
||||
#![feature(coerce_unsized)]
|
||||
#![feature(dispatch_from_dyn)]
|
||||
#![feature(inline_const)]
|
||||
#![feature(lint_reasons)]
|
||||
#![feature(unsize)]
|
||||
|
||||
|
|
|
|||
|
|
@ -14,7 +14,7 @@
|
|||
#[doc(no_inline)]
|
||||
pub use core::pin::Pin;
|
||||
|
||||
pub use crate::alloc::{flags::*, vec_ext::VecExt, Box, KBox, KVBox, VBox};
|
||||
pub use crate::alloc::{flags::*, vec_ext::VecExt, Box, KBox, KVBox, KVVec, KVec, VBox, VVec};
|
||||
|
||||
#[doc(no_inline)]
|
||||
pub use alloc::vec::Vec;
|
||||
|
|
|
|||
Loading…
Reference in a new issue