Deallocator running out of stack space

[jjwhitney]

Deallocation of object chains seems to require stack space proportional to the size of the chain. The following example, for instance, fails with a "ran out of stack" error:

extern mod extra;

use extra::dlist::DList;
use extra::container::Deque;

fn main() {
    let mut m = ~ DList::new::<int>();

    for _ in range(0, 17000000) {
        m.push_front(0);
    }
    println("This line is printed");
    // Does not exit cleanly: "ran out of stack"
}

[brson]

This is a problem for the new scheduler that doesn't yet implement split stacks. The Node dtor tail-recurses and the dlist benchmarks overflow the stack.

[brson]

Fixed.