What is the Correct way to Malloc in @nogc section?

[Foo via Digitalmars-d-learn]

On Thursday, 12 February 2015 at 23:27:51 UTC, Kitt wrote:
> I'm currently trying to write a personal Associate Array class 
> that can be used in @nogc sections. Obviously, this means I'll 
> want to use malloc/free, however I'm not sure what the 
> "Correct" way to do this is. In a few places online I've seen 
> code for custom "_new" and "_delete" functions similar to this:
>
> [code]
> T _new(T, Args...) (Args args) {
>     size_t objSize;
> 	static if(is (ValType == class))
> 	    objSize = __traits(classInstanceSize, T);
> 	else
> 	    objSize = T.sizeof;
>
>     void* tmp = core.stdc.stdlib.malloc(objSize);
>     if (!tmp) throw new Exception("Memory allocation failed");
>     void[] mem = tmp[0..objSize];
>     T obj = emplace!(T, Args)(mem, args);
>     return obj;
> }
>
> void _delete(T)(T obj) {
>     clear(obj);
>     core.stdc.stdlib.free(cast(void*)obj);
> }
> [/code]
>
> The Exception obviously uses the GC, and would need to be 
> replaced with a printf or something; however, emplace doesn't 
> have a @nogc replacement that I know of. What I'd like to know, 
> from people much more knowledgeable about the ins and outs of 
> D, is what the "Best" or "Correct" way to allocate and 
> deallocate within @nogc sections?
>
> PS: Tangentially related, what hashing algorithm does D use? 
> I've seen people suggest using typeid(object).toHash(&object); 
> however, toHash isn't @nogc, so I need to write my own Hashing 
> function. For the sake of consistency and peace of mind, I'd 
> really like to match mine as closely to Ds internal one as 
> possible.

This is something I've done recently.
Would be glad if my code will help you:
https://github.com/Dgame/m3
Especially the m3.d module could be useful for you.