diff options
Diffstat (limited to 'library/alloc/src/collections/vec_deque/mod.rs')
-rw-r--r-- | library/alloc/src/collections/vec_deque/mod.rs | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/library/alloc/src/collections/vec_deque/mod.rs b/library/alloc/src/collections/vec_deque/mod.rs index e3f4deb08..2a57dad89 100644 --- a/library/alloc/src/collections/vec_deque/mod.rs +++ b/library/alloc/src/collections/vec_deque/mod.rs @@ -12,11 +12,17 @@ use core::fmt; use core::hash::{Hash, Hasher}; use core::iter::{repeat_with, FromIterator}; use core::marker::PhantomData; -use core::mem::{self, ManuallyDrop, MaybeUninit}; +use core::mem::{ManuallyDrop, MaybeUninit, SizedTypeProperties}; use core::ops::{Index, IndexMut, Range, RangeBounds}; use core::ptr::{self, NonNull}; use core::slice; +// This is used in a bunch of intra-doc links. +// FIXME: For some reason, `#[cfg(doc)]` wasn't sufficient, resulting in +// failures in linkchecker even though rustdoc built the docs just fine. +#[allow(unused_imports)] +use core::mem; + use crate::alloc::{Allocator, Global}; use crate::collections::TryReserveError; use crate::collections::TryReserveErrorKind; @@ -177,7 +183,7 @@ impl<T, A: Allocator> VecDeque<T, A> { /// Marginally more convenient #[inline] fn cap(&self) -> usize { - if mem::size_of::<T>() == 0 { + if T::IS_ZST { // For zero sized types, we are always at maximum capacity MAXIMUM_ZST_CAPACITY } else { @@ -3038,7 +3044,7 @@ impl<T, A: Allocator> From<Vec<T, A>> for VecDeque<T, A> { /// `Vec<T>` came from `From<VecDeque<T>>` and hasn't been reallocated. fn from(mut other: Vec<T, A>) -> Self { let len = other.len(); - if mem::size_of::<T>() == 0 { + if T::IS_ZST { // There's no actual allocation for ZSTs to worry about capacity, // but `VecDeque` can't handle as much length as `Vec`. assert!(len < MAXIMUM_ZST_CAPACITY, "capacity overflow"); @@ -3124,7 +3130,7 @@ impl<T, const N: usize> From<[T; N]> for VecDeque<T> { fn from(arr: [T; N]) -> Self { let mut deq = VecDeque::with_capacity(N); let arr = ManuallyDrop::new(arr); - if mem::size_of::<T>() != 0 { + if !<T>::IS_ZST { // SAFETY: VecDeque::with_capacity ensures that there is enough capacity. unsafe { ptr::copy_nonoverlapping(arr.as_ptr(), deq.ptr(), N); |