// option. This file may not be copied, modified, or distributed
// except according to those terms.
-// Check that `pub extern crate` gives a warning.
-
+#![feature(rustc_attrs)]
pub extern crate core; //~WARN `pub extern crate` does not work
-//~^ ERROR core
-fn main() {
-}
+#[rustc_error]
+fn main() {} //~ ERROR: compilation successful