1warning: trait-associated function `from_iter` will become ambiguous in Rust 2021 2 --> $DIR/generic-type-collision.rs:15:5 3 | 4LL | <Vec<i32>>::from_iter(None); 5 | ^^^^^^^^^^^^^^^^^^^^^ help: disambiguate the associated function: `<Vec<i32> as MyTrait<_>>::from_iter` 6 | 7note: the lint level is defined here 8 --> $DIR/generic-type-collision.rs:4:9 9 | 10LL | #![warn(rust_2021_prelude_collisions)] 11 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 12 = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021! 13 = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/prelude.html> 14 15warning: 1 warning emitted 16 17