error[E0496]: lifetime name `'a` shadows a lifetime name that is already in scope
  --> $DIR/E0496.rs:6:10
   |
LL | impl<'a> Foo<'a> {
   |      -- first declared here
LL |     fn f<'a>(x: &'a i32) {
   |          ^^ lifetime `'a` already in scope

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0496`.