error[E0599]: no method named `cmp` found for type parameter `T` in the current scope
  --> $DIR/method-on-unbounded-type-param.rs:2:7
   |
LL | fn f<T>(a: T, b: T) -> std::cmp::Ordering {
   |      - method `cmp` not found for this type parameter
LL |     a.cmp(&b)
   |       ^^^ method cannot be called on `T` due to unsatisfied trait bounds
   |
   = help: items from traits can only be used if the type parameter is bounded by the trait
help: the following traits define an item `cmp`, perhaps you need to restrict type parameter `T` with one of them:
   |
LL | fn f<T: Iterator>(a: T, b: T) -> std::cmp::Ordering {
   |       ++++++++++
LL | fn f<T: Ord>(a: T, b: T) -> std::cmp::Ordering {
   |       +++++

error[E0599]: the method `cmp` exists for reference `&T`, but its trait bounds were not satisfied
  --> $DIR/method-on-unbounded-type-param.rs:5:10
   |
LL |     (&a).cmp(&b)
   |          ^^^ method cannot be called on `&T` due to unsatisfied trait bounds
   |
   = note: the following trait bounds were not satisfied:
           `T: Ord`
           which is required by `&T: Ord`
           `&T: Iterator`
           which is required by `&mut &T: Iterator`
           `T: Iterator`
           which is required by `&mut T: Iterator`
   = help: items from traits can only be used if the type parameter is bounded by the trait
help: the following traits define an item `cmp`, perhaps you need to restrict type parameter `T` with one of them:
   |
LL | fn g<T: Iterator>(a: T, b: T) -> std::cmp::Ordering {
   |       ++++++++++
LL | fn g<T: Ord>(a: T, b: T) -> std::cmp::Ordering {
   |       +++++

error[E0599]: the method `cmp` exists for reference `&T`, but its trait bounds were not satisfied
  --> $DIR/method-on-unbounded-type-param.rs:8:7
   |
LL |     a.cmp(&b)
   |       ^^^ method cannot be called on `&T` due to unsatisfied trait bounds
   |
   = note: the following trait bounds were not satisfied:
           `T: Ord`
           which is required by `&T: Ord`
           `&T: Iterator`
           which is required by `&mut &T: Iterator`
           `T: Iterator`
           which is required by `&mut T: Iterator`
   = help: items from traits can only be used if the type parameter is bounded by the trait
help: the following traits define an item `cmp`, perhaps you need to restrict type parameter `T` with one of them:
   |
LL | fn h<T: Iterator>(a: &T, b: T) -> std::cmp::Ordering {
   |       ++++++++++
LL | fn h<T: Ord>(a: &T, b: T) -> std::cmp::Ordering {
   |       +++++

error[E0599]: the method `cmp` exists for struct `Box<dyn T>`, but its trait bounds were not satisfied
  --> $DIR/method-on-unbounded-type-param.rs:14:7
   |
LL | trait T {}
   | ------- doesn't satisfy `dyn T: Iterator` or `dyn T: Ord`
...
LL |     x.cmp(&x);
   |       ^^^ method cannot be called on `Box<dyn T>` due to unsatisfied trait bounds
   |
   = note: the following trait bounds were not satisfied:
           `dyn T: Iterator`
           which is required by `Box<dyn T>: Iterator`
           `dyn T: Ord`
           which is required by `Box<dyn T>: Ord`
           `Box<dyn T>: Iterator`
           which is required by `&mut Box<dyn T>: Iterator`
           `dyn T: Iterator`
           which is required by `&mut dyn T: Iterator`
   = help: items from traits can only be used if the trait is implemented and in scope
   = note: the following traits define an item `cmp`, perhaps you need to implement one of them:
           candidate #1: `Ord`
   = note: the trait `Iterator` defines an item `cmp`, but is explicitly unimplemented

error: aborting due to 4 previous errors

For more information about this error, try `rustc --explain E0599`.