// run-pass // aux-build:extern-crosscrate-source.rs // ignore-wasm32-bare no libc to test ffi with #![feature(rustc_private)] extern crate externcallback; extern crate libc; fn fact(n: libc::uintptr_t) -> libc::uintptr_t { unsafe { println!("n = {}", n); externcallback::rustrt::rust_dbg_call(externcallback::cb, n) } } pub fn main() { let result = fact(10); println!("result = {}", result); assert_eq!(result, 3628800); }