rust/src/test/compile-fail/regions-creating-enums4.rs

enum ast {
    num(uint),
    add(&ast, &ast)
}

fn mk_add_bad2(x: &a/ast, y: &a/ast, z: &ast) -> ast {
    add(x, y)
         //~^ ERROR cannot infer an appropriate lifetime
}

fn main() {
}