Implicit trait coercions with moves will segfault

[alexcrichton]

This code segfaults:

use std::io;

fn foo(mut a: ~Writer) {
    a.write(bytes!("Hello\n"));
}

fn main() {
    let out = io::stdout();
    foo(~out);
}

[alexcrichton]

Nominating, this is very bad.

[alexcrichton]

This code works:

use std::io;

fn foo(mut a: ~Writer) {
    a.write(bytes!("Hello\n"));
}

fn main() {
    foo(~io::stdout());
}

[pnkfelix]

Assigning to P-high.