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[rust.git] / src / liballoc / vec.rs

diff --git a/src/liballoc/vec.rs b/src/liballoc/vec.rs
index 1265d0e56b576ceed08c1f12091a4abd8053b043..2f56898f4e9b66e43823aa765140932a0e082028 100644 (file)
--- a/src/liballoc/vec.rs
+++ b/src/liballoc/vec.rs
@@ -491,7 +491,7 @@ pub fn capacity(&self) -> usize {
     ///
     /// # Panics
     ///
-    /// Panics if the new capacity overflows `usize`.
+    /// Panics if the new capacity exceeds `isize::MAX` bytes.
     ///
     /// # Examples
     ///
@@ -1188,7 +1188,7 @@ pub fn dedup_by<F>(&mut self, same_bucket: F)
     ///
     /// # Panics
     ///
-    /// Panics if the number of elements in the vector overflows a `usize`.
+    /// Panics if the new capacity exceeds `isize::MAX` bytes.
     ///
     /// # Examples
     ///
@@ -1274,11 +1274,10 @@ unsafe fn append_elements(&mut self, other: *const [T]) {
     /// Creates a draining iterator that removes the specified range in the vector
     /// and yields the removed items.
     ///
-    /// Note 1: The element range is removed even if the iterator is only
-    /// partially consumed or not consumed at all.
-    ///
-    /// Note 2: It is unspecified how many elements are removed from the vector
-    /// if the `Drain` value is leaked.
+    /// When the iterator **is** dropped, all elements in the range are removed
+    /// from the vector, even if the iterator was not fully consumed. If the
+    /// iterator **is not** dropped (with [`mem::forget`] for example), it is
+    /// unspecified how many elements are removed.
     ///
     /// # Panics
     ///
@@ -1801,6 +1800,21 @@ impl<T: Clone> SpecFromElem for T {
     }
 }
 
+impl SpecFromElem for i8 {
+    #[inline]
+    fn from_elem(elem: i8, n: usize) -> Vec<i8> {
+        if elem == 0 {
+            return Vec { buf: RawVec::with_capacity_zeroed(n), len: n };
+        }
+        unsafe {
+            let mut v = Vec::with_capacity(n);
+            ptr::write_bytes(v.as_mut_ptr(), elem as u8, n);
+            v.set_len(n);
+            v
+        }
+    }
+}
+
 impl SpecFromElem for u8 {
     #[inline]
     fn from_elem(elem: u8, n: usize) -> Vec<u8> {
@@ -1845,7 +1859,6 @@ fn is_zero(&self) -> bool {
     };
 }
 
-impl_is_zero!(i8, |x| x == 0);
 impl_is_zero!(i16, |x| x == 0);
 impl_is_zero!(i32, |x| x == 0);
 impl_is_zero!(i64, |x| x == 0);