Disable GC entirely

[Manipulator]

I just re-read the "Doom3 Source Code Review" by Fabien Sanglard 
(http://fabiensanglard.net/doom3/) and apparently they don't use 
the Standard C++ library. "The engine does not use the Standard 
C++ Library: All containers (map,linked list...) are 
re-implemented but libc is extensively used."
I certainly feel that there is room for improvement, like 
optimizing the GC, define a GC-free subset of Phobos etc. But it 
seems like if you're writing really performance critical realtime 
software most likely you've to implement everything bottom up to 
get the level of control.

Secondly it seems like it's most often cheaper to just throw 
faster hardware at a problem.
"You can do tricks to address any one of them; but I pretty 
strongly believe that with all of these things that are 
troublesome in graphics, rather than throwing really complex 
algorithms at them, they will eventually fall to raw processing 
power."(http://fabiensanglard.net/doom3/interviews.php)

My 2p.