#![feature(no_core, lang_items)] #![no_core] #[lang="sized"] trait Sized {} #[lang="add"] trait Add {} impl Add for i32 {} fn main() { let x = 5 + 6; //~^ ERROR cannot add `i32` to `{integer}` let y = 5i32 + 6i32; //~^ ERROR cannot add `i32` to `i32` }