src/test/ui/E0705.stderr

   1 warning[E0705]: the feature `impl_header_lifetime_elision` is included in the Rust 2018 edition
   2   --> $DIR/E0705.rs:13:12
   3    |
   4 LL | #![feature(impl_header_lifetime_elision)]
   5    |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   6