tests/ui/generics/generic-extern.rs - toolchain/rustc - Git at Google

 extern "C" {
     fn foo<T>(); //~ ERROR foreign items may not have type parameters
 }

 fn main() {
     foo::<i32>();
 }
	extern "C" {
	fn foo<T>(); //~ ERROR foreign items may not have type parameters
	}

	fn main() {
	foo::<i32>();
	}