diff options
Diffstat (limited to 'library/alloc/src/macros.rs')
| -rw-r--r-- | library/alloc/src/macros.rs | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/library/alloc/src/macros.rs b/library/alloc/src/macros.rs index 5198bf297..4c6ae8f25 100644 --- a/library/alloc/src/macros.rs +++ b/library/alloc/src/macros.rs @@ -48,6 +48,8 @@ macro_rules! vec { ); ($($x:expr),+ $(,)?) => ( $crate::__rust_force_expr!(<[_]>::into_vec( + // This rustc_box is not required, but it produces a dramatic improvement in compile + // time when constructing arrays with many elements. #[rustc_box] $crate::boxed::Box::new([$($x),+]) )) |