error[E0658]: use of unstable library feature 'unstable_default'
  --> $DIR/generics-default-stability-trait.rs:16:13
   |
LL | impl Trait1<usize> for S {
   |             ^^^^^
   |
   = help: add `#![feature(unstable_default)]` to the crate attributes to enable

error[E0658]: use of unstable library feature 'unstable_default'
  --> $DIR/generics-default-stability-trait.rs:20:13
   |
LL | impl Trait1<isize> for S {
   |             ^^^^^
   |
   = help: add `#![feature(unstable_default)]` to the crate attributes to enable

error[E0658]: use of unstable library feature 'unstable_default'
  --> $DIR/generics-default-stability-trait.rs:24:13
   |
LL | impl Trait2<usize> for S {
   |             ^^^^^
   |
   = help: add `#![feature(unstable_default)]` to the crate attributes to enable

error: aborting due to 3 previous errors

For more information about this error, try `rustc --explain E0658`.