1 error[E0658]: auto traits are experimental and possibly buggy (see issue #13231)
2 --> $DIR/feature-gate-optin-builtin-traits.rs:20:1
4 LL | auto trait AutoDummyTrait {}
5 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
7 = help: add #![feature(optin_builtin_traits)] to the crate attributes to enable
9 error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now (see issue #13231)
10 --> $DIR/feature-gate-optin-builtin-traits.rs:23:1
12 LL | impl !DummyTrait for DummyStruct {}
13 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
15 = help: add #![feature(optin_builtin_traits)] to the crate attributes to enable
17 error: aborting due to 2 previous errors
19 For more information about this error, try `rustc --explain E0658`.