error[E0283]: type annotations needed
  --> $DIR/overflow-computing-ambiguity.rs:15:5
   |
LL |     hello();
   |     ^^^^^ cannot infer type of the type parameter `T` declared on the function `hello`
   |
   = note: cannot satisfy `_: Hello`
help: the following types implement trait `Hello`
  --> $DIR/overflow-computing-ambiguity.rs:8:1
   |
LL | impl<'a, T> Hello for Foo<'a, &'a T> where Foo<'a, T>: Hello {}
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `Foo<'a, &'a T>`
LL |
LL | impl Hello for Foo<'static, i32> {}
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `Foo<'static, i32>`
note: required by a bound in `hello`
  --> $DIR/overflow-computing-ambiguity.rs:12:13
   |
LL | fn hello<T: Hello>() {}
   |             ^^^^^ required by this bound in `hello`
help: consider specifying the generic argument
   |
LL |     hello::<T>();
   |          +++++

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0283`.