Merging upstream version 1.71.1+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 3 insertions, 5 deletions

diff --git a/library/alloc/src/vec/drain.rs b/library/alloc/src/vec/drain.rs
index 2b1a787cc..f0b63759a 100644
--- a/library/alloc/src/vec/drain.rs
+++ b/library/alloc/src/vec/drain.rs
@@ -16,7 +16,7 @@ use super::Vec;
 ///
 /// ```
 /// let mut v = vec![0, 1, 2];
-/// let iter: std::vec::Drain<_> = v.drain(..);
+/// let iter: std::vec::Drain<'_, _> = v.drain(..);
 /// ```
 #[stable(feature = "drain", since = "1.6.0")]
 pub struct Drain<
@@ -112,9 +112,7 @@ impl<'a, T, A: Allocator> Drain<'a, T, A> {
             let unyielded_ptr = this.iter.as_slice().as_ptr();
 
             // ZSTs have no identity, so we don't need to move them around.
-            let needs_move = mem::size_of::<T>() != 0;
-
-            if needs_move {
+            if !T::IS_ZST {
                 let start_ptr = source_vec.as_mut_ptr().add(start);
 
                 // memmove back unyielded elements
@@ -197,7 +195,7 @@ impl<T, A: Allocator> Drop for Drain<'_, T, A> {
             }
         }
 
-        let iter = mem::replace(&mut self.iter, (&mut []).iter());
+        let iter = mem::take(&mut self.iter);
         let drop_len = iter.len();
 
         let mut vec = self.vec;