error: expected identifier, found reserved identifier `_`
  --> $DIR/infer-arg-test.rs:7:17
   |
LL | struct BadInfer<_>;
   |                 ^ expected identifier, found reserved identifier

error: expected identifier, found reserved identifier `_`
  --> $DIR/infer-arg-test.rs:13:17
   |
LL | fn bad_infer_fn<_>() {}
   |                 ^ expected identifier, found reserved identifier

error[E0392]: type parameter `_` is never used
  --> $DIR/infer-arg-test.rs:7:17
   |
LL | struct BadInfer<_>;
   |                 ^ unused type parameter
   |
   = help: consider removing `_`, referring to it in a field, or using a marker such as `PhantomData`
   = help: if you intended `_` to be a const parameter, use `const _: /* Type */` instead

error[E0107]: struct takes 2 generic arguments but 3 generic arguments were supplied
  --> $DIR/infer-arg-test.rs:18:10
   |
LL |   let a: All<_, _, _>;
   |          ^^^     --- help: remove the unnecessary generic argument
   |          |
   |          expected 2 generic arguments
   |
note: struct defined here, with 2 generic parameters: `T`, `N`
  --> $DIR/infer-arg-test.rs:3:8
   |
LL | struct All<'a, T, const N: usize> {
   |        ^^^     -  --------------

error: aborting due to 4 previous errors

Some errors have detailed explanations: E0107, E0392.
For more information about an error, try `rustc --explain E0107`.