D's New GC and Object Allocation Pools

[Damian via Digitalmars-d]

On Sunday, 26 October 2014 at 03:37:47 UTC, Maxime 
Chevalier-Boisvert wrote:
> Hello,
>
> I was wondering if there have been updates regarding Andrei's 
> announcement that he would rewrite the D garbage collector. Is 
> there any kind of timeline for when a new version of the GC can 
> be expected?
>
> I also wanted to ask if there was an implementation of an 
> object pool in the standard library. If not, I'm wondering what 
> the best way to implement this is. Is there any way to overload 
> new and destroy?
>
> I was thinking of using the templated emplace operator from 
> std.conv to allocate class objects into a large flat array, and 
> to derive pool-allocated classes from a PoolObject base class. 
> This base class would contain linked list pointers to implement 
> a free list, as well as templated static methods to allocate 
> and free the objects. Any advice welcome.

For your object pool, why not just create functions, alloc and 
free, instead of trying to override them - something like below

version (USE_GC)
{
   import core.memory;
}
else
{
   import core.stdc.stdlib: malloc, free;
}

struct MemPool
{
   void* alloc(size_t size, bool usePool = true) nothrow
   {
     version (USE_GC) return GC.malloc(size);
     else malloc(size);
   }

   void Free(void* p) nothrow
   {
     version (USE_GC) GC.free(p);
     else free(p);
   }
}