From: Eric Hodel <drbrain@...7.net>
Date: 2008-07-31T09:40:12+09:00
Subject: Re: gc doesn't collect?

On Jul 30, 2008, at 17:13 PM, Roger Pack wrote:
> Any ideas why:
>
> 1.times { a = 'a'*1000};
> 30.times { GC.start };
> print ObjectSpace.each_object{|o| print o}
>
> prints out 'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa...' despite the fact that
> the a's should have been collected?

Ruby's garbage collector walks the C stack looking for values that  
appear to point to the ruby heap.  Ruby thinks you still have a  
reference to your string because of this.