error[E0283]: type annotations needed
  --> $DIR/multidispatch-convert-ambig-dest.rs:26:5
   |
LL |     test(22, std::default::Default::default());
   |     ^^^^ -- type must be known at this point
   |     |
   |     cannot infer type of the type parameter `U` declared on the function `test`
   |
note: multiple `impl`s satisfying `i32: Convert<_>` found
  --> $DIR/multidispatch-convert-ambig-dest.rs:8:1
   |
LL | impl Convert<i8> for i32 {
   | ^^^^^^^^^^^^^^^^^^^^^^^^
...
LL | impl Convert<i16> for i32 {
   | ^^^^^^^^^^^^^^^^^^^^^^^^^
note: required by a bound in `test`
  --> $DIR/multidispatch-convert-ambig-dest.rs:21:11
   |
LL | fn test<T,U>(_: T, _: U)
   |    ---- required by a bound in this function
LL | where T : Convert<U>
   |           ^^^^^^^^^^ required by this bound in `test`
help: consider specifying the generic arguments
   |
LL |     test::<i32, U>(22, std::default::Default::default());
   |         ++++++++++

error: aborting due to 1 previous error

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