error: `default` is not followed by an item
  --> $DIR/default.rs:23:5
   |
LL |     default pub fn foo<T: Default>() -> T { T::default() }
   |     ^^^^^^^ the `default` qualifier
   |
   = note: only `fn`, `const`, `type`, or `impl` items may be prefixed by `default`

error: non-item in item list
  --> $DIR/default.rs:23:13
   |
LL | impl Foo for u32 {
   |                  - item list starts here
LL |     default pub fn foo<T: Default>() -> T { T::default() }
   |             ^^^ non-item starts here
...
LL | }
   | - item list ends here

error[E0449]: visibility qualifiers are not permitted here
  --> $DIR/default.rs:17:5
   |
LL |     pub default fn foo<T: Default>() -> T {
   |     ^^^
   |
   = note: trait items always share the visibility of their trait

warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes
  --> $DIR/default.rs:3:12
   |
LL | #![feature(specialization)]
   |            ^^^^^^^^^^^^^^
   |
   = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
   = help: consider using `min_specialization` instead, which is more stable and complete
   = note: `#[warn(incomplete_features)]` on by default

error[E0046]: not all trait items implemented, missing: `foo`
  --> $DIR/default.rs:22:1
   |
LL |     fn foo<T: Default>() -> T;
   |     -------------------------- `foo` from trait
...
LL | impl Foo for u32 {
   | ^^^^^^^^^^^^^^^^ missing `foo` in implementation

error: aborting due to 4 previous errors; 1 warning emitted

Some errors have detailed explanations: E0046, E0449.
For more information about an error, try `rustc --explain E0046`.