error[E0284]: type annotations needed for `Foo<_>`
  --> $DIR/doesnt_infer.rs:13:9
   |
LL |     let foo = Foo::foo();
   |         ^^^   ---------- type must be known at this point
   |
note: required by a const generic parameter in `Foo::<N>::foo`
  --> $DIR/doesnt_infer.rs:5:6
   |
LL | impl<const N: u32> Foo<N> {
   |      ^^^^^^^^^^^^ required by this const generic parameter in `Foo::<N>::foo`
LL |     fn foo() -> Self {
   |        --- required by a bound in this associated function
help: consider giving `foo` an explicit type, where the value of const parameter `N` is specified
   |
LL |     let foo: Foo<N> = Foo::foo();
   |            ++++++++

error[E0284]: type annotations needed for `Foo<_>`
  --> $DIR/doesnt_infer.rs:13:9
   |
LL |     let foo = Foo::foo();
   |         ^^^   --- type must be known at this point
   |
note: required by a const generic parameter in `Foo`
  --> $DIR/doesnt_infer.rs:3:12
   |
LL | struct Foo<const N: u32 = 2>;
   |            ^^^^^^^^^^^^^^^^ required by this const generic parameter in `Foo`
help: consider giving `foo` an explicit type, where the value of const parameter `N` is specified
   |
LL |     let foo: Foo<N> = Foo::foo();
   |            ++++++++

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0284`.