trait A { } struct B<'a, T:'a>(&'a (dyn A + 'a)); trait X { } impl<'a, T> X for B<'a, T> {} fn g<'a, T: 'static>(v: Box + 'a>) -> Box { Box::new(B(&*v)) as Box //~^ ERROR lifetime may not live long enough //~| ERROR cannot return value referencing local data `*v` [E0515] } fn main() { }