tests/ui/macros/malformed_macro_lhs.rs - rust-lang/rust - Git at Google

 macro_rules! my_precioooous {
     t => (1); //~ ERROR invalid macro matcher
 }

 fn main() {
     my_precioooous!();
 }
	macro_rules! my_precioooous {
	t => (1); //~ ERROR invalid macro matcher
	}

	fn main() {
	my_precioooous!();
	}