Re: [boost] request for interest in a garbage collection library

Subject: Re: [boost] request for interest in a garbage collection library
From: Mathias Gaunard (mathias.gaunard_at_[hidden])
Date: 2009-04-18 07:16:31

Jonas Persson wrote:

> The following example gives an access violation on windows:
> 
> ----------------------------------------------
>   class Foo : public gc_object<Foo> {
>   public:
>     gc_ptr<Foo> m_next;
>     std::string m_name;
> 
>     Foo(std::string name) : m_name(name) {}
> 
>     ~Foo() {
>       m_next->lastGoodbye();
>     }
> 
>     void lastGoodbye() { std::cout << "Bye " << m_name; }
>   };
>   void test_cycle() {
>     gc_ptr<Foo> foo1 = new Foo("foo 1");
>     foo1->m_next = new Foo("foo 2");
>     foo1->m_next->m_next = foo1;
> 
>     foo1 = 0;
>     gc::collect();
>   }

So that library overloads operator new, meaning all memory becomes 
garbage collected, unlike what I understood from what was answered to 
one of my other posts.
I even wonder how gc_ptr<T>::gc_ptr::(T*) can be a safe constructor at all.

A fairly terrible design, that has a lot of shortcomings, some of which 
where raised when talking of Boehm GC (basically, bad integration).

The funny thing is that the right way to do GC in C++ has been known for 
a long time, but for some reason people still want to do it some other way.
C++/CLI, despite its evilness, does it right. Bastek's library (SGCL) 
seems to do it somewhat right too.