src/tools/clippy/tests/ui/box_vec.stderr

   1 error: you seem to be trying to use `Box<Vec<T>>`. Consider using just `Vec<T>`
   2   --> $DIR/box_vec.rs:17:18
   3    |
   4 17 | pub fn test(foo: Box<Vec<bool>>) {
   5    |                  ^^^^^^^^^^^^^^
   6    |
   7    = note: `-D box-vec` implied by `-D warnings`
   8    = help: `Vec<T>` is already on the heap, `Box<Vec<T>>` makes an extra allocation.
   9