use core::alloc::LayoutError;
use core::cmp;
use core::intrinsics;
-use core::mem::{self, ManuallyDrop, MaybeUninit};
+use core::mem::{self, ManuallyDrop, MaybeUninit, SizedTypeProperties};
use core::ops::Drop;
use core::ptr::{self, NonNull, Unique};
use core::slice;
#[cfg(not(no_global_oom_handling))]
fn allocate_in(capacity: usize, init: AllocInit, alloc: A) -> Self {
// Don't allocate here because `Drop` will not deallocate when `capacity` is 0.
- if mem::size_of::<T>() == 0 || capacity == 0 {
+ if T::IS_ZST || capacity == 0 {
Self::new_in(alloc)
} else {
// We avoid `unwrap_or_else` here because it bloats the amount of
/// This will always be `usize::MAX` if `T` is zero-sized.
#[inline(always)]
pub fn capacity(&self) -> usize {
- if mem::size_of::<T>() == 0 { usize::MAX } else { self.cap }
+ if T::IS_ZST { usize::MAX } else { self.cap }
}
/// Returns a shared reference to the allocator backing this `RawVec`.
}
fn current_memory(&self) -> Option<(NonNull<u8>, Layout)> {
- if mem::size_of::<T>() == 0 || self.cap == 0 {
+ if T::IS_ZST || self.cap == 0 {
None
} else {
// We have an allocated chunk of memory, so we can bypass runtime
// This is ensured by the calling contexts.
debug_assert!(additional > 0);
- if mem::size_of::<T>() == 0 {
+ if T::IS_ZST {
// Since we return a capacity of `usize::MAX` when `elem_size` is
// 0, getting to here necessarily means the `RawVec` is overfull.
return Err(CapacityOverflow.into());
// `grow_amortized`, but this method is usually instantiated less often so
// it's less critical.
fn grow_exact(&mut self, len: usize, additional: usize) -> Result<(), TryReserveError> {
- if mem::size_of::<T>() == 0 {
+ if T::IS_ZST {
// Since we return a capacity of `usize::MAX` when the type size is
// 0, getting to here necessarily means the `RawVec` is overfull.
return Err(CapacityOverflow.into());