trait Trait1<'a> {} trait Trait2<'a, 'b> {} fn f() where for<'a> dyn Trait1<'a>: Trait1<'a>, // OK (dyn for<'a> Trait1<'a>): Trait1<'a>, //~^ ERROR use of undeclared lifetime name `'a` for<'a> dyn for<'b> Trait2<'a, 'b>: Trait2<'a, 'b>, //~^ ERROR use of undeclared lifetime name `'b` {} fn main() {}