new D2.0 + C++ language

[BCS]

Hello Christopher,

> 
> It would be cool if the GC could watch for what pages have been
> written to since the last collection and only bother looking through
> them. That would require some additional accounting. On Windows,
> there's a system call GetWriteWatch that works in that regard, but on
> Linux, the only solution I've seen is marking the memory readonly and
> trapping SIGSEGV. That would be pretty expensive.
> 

http://libsigsegv.sourceforge.net/

"""
What is libsigsegv?

This is a library for handling page faults in user mode. A page fault occurs 
when a program tries to access to a region of memory that is currently not 
available. Catching and handling a page fault is a useful technique for implementing:

...
    * generational garbage collectors,
"""