Best properly way to destroy a 2 dimensional array?

[Jonathan Villa via Digitalmars-d-learn]

On Thursday, 7 April 2016 at 16:13:59 UTC, Steven Schveighoffer 
wrote:
> On 4/6/16 3:54 PM, Jonathan Villa wrote:
>
> You are likely running into the GC being conservative. You are 
> also possibly running into an issue where you are expecting the 
> compiler to do something with the stack where it may do 
> something else. A classic question that is asked on D forums 
> all the time is why when you null some variable and then call 
> GC collect, the memory isn't collected. The answer is because 
> quite possibly the value is still in a register, and the 
> registers must be scanned too.
>
> As for conservatism, if you generate a 1-million element array 
> of pointers (each element has a pointer in it), then you have 
> some random stack variable that "happens" to point into that 
> giant array (more likely in 32-bit systems), then both the 
> array, and all it's pointing at gets saved.
> 
> -Steve

Good, I compiled the program in 64 bit mode (-m64) and now it 
release memory normally like in Debian.

I would like to know where can I learn more about the 'register' 
or the GC for the D so I can avoid future issues.

JV.