thread and gc.fullCollect

[Ant]

I don't get this.

If I run this program count is printed about 50 times
and takes 5 seconds to complete as expected.

but if uncomment line 19 count is printed only twice and the program 
exist almost immediately...

Why is that?

Ant

private import std.gc;
private import std.thread;
private import std.c.time;
private import std.stdio;

class Foo
{
	int count;
	this()
	{
		Thread ft = new Thread(&foo);

		ft.start();
		std.gc.fullCollect();	// ok
		
		while ( ft.getState() != Thread.TS.TERMINATED )
		{
// line 19		std.gc.fullCollect();
			writefln("Count = %s ", count++);
			std.c.time.usleep(100000);
		}
	}
	int foo()
	{
		std.c.time.sleep(5);
		return true;
	}
}

void main()
{
	new Foo();
}