Demonstrates a bug in c84890. Under OS X 10.9, crashes in receive code with null pointer.

boring09.rs

// Rust IO Test
// Based on samples presented in Rob Pike's Go Concurrency talk

use std::libc::funcs::posix88::unistd::sleep;
use std::rand::random;
use std::comm::{Chan, Port};

struct Message {
    string:       ~str,
    wait_chan:    Chan<bool>,
    wait_port:    Port<bool>,
}

fn fan_in(p1: Port<~Message>, p2: Port<~Message>) -> Port<~Message> {

    let (port, chan) = Chan::<~Message>::new();

    let c1 = chan.clone();
    spawn(proc() for d in p1.iter() { c1.send(d); });

    let c2 = chan.clone();
    spawn(proc() for d in p2.iter() { c2.send(d); });

    return port;
}

// Returns a port for strings
fn boring(msg: ~str) -> Port<~Message> {

    let (wait_port, wait_chan) = Chan::<bool>::new();

    let (port, chan) = Chan::<~Message>::new();

    spawn( proc()
        for i in range(0, 5) {

            let m = ~Message {
                string: format!("{} {}", msg, i),
                wait_chan: wait_chan,
                wait_port: wait_port,
            };

            chan.send(m);

            unsafe {
                sleep((random::<u8>() % 3) as u32);
            }

            wait_port.recv();
        }
    );
    return port;
}

fn main() {

    let port = fan_in(boring(~"Joe"), boring(~"Ann"));

    for i in range(0, 5) {
            let msg1 = port.recv(); println!("{}", msg1.string);
            let msg2 = port.recv(); println!("{}", msg2.string);
     
            msg1.wait_chan.send(true);
            msg2.wait_chan.send(true);
    }

    println!("You're all boring; I'm leaving.");
}