Auto merge of #26904 - bluss:no-repeat, r=alexcrichton

In a followup to PR #26849, improve one more location for I/O where
we can use `Vec::resize` to ensure better performance when zeroing
buffers.

Use the `vec![elt; n]` macro everywhere we can in the tree. It replaces
`repeat(elt).take(n).collect()` which is more verbose, requires type
hints, and right now produces worse code. `vec![]` is preferable for vector
initialization.

The `vec![]` replacement touches upon one I/O path too, Stdin::read
for windows, and that should be a small improvement.

r? @alexcrichton 

1 files changed, 1 insertions, 1 deletions

diff --git a/src/libcollections/bit.rs b/src/libcollections/bit.rs
index a8d638028be..3a4cfbba65f 100644
--- a/src/libcollections/bit.rs
+++ b/src/libcollections/bit.rs
@@ -283,7 +283,7 @@ impl BitVec {
     pub fn from_elem(nbits: usize, bit: bool) -> BitVec {
         let nblocks = blocks_for_bits(nbits);
         let mut bit_vec = BitVec {
-            storage: repeat(if bit { !0 } else { 0 }).take(nblocks).collect(),
+            storage: vec![if bit { !0 } else { 0 }; nblocks],
             nbits: nbits
         };
         bit_vec.fix_last_block();