A few considerations on garbage collection

[Orvid King via Digitalmars-d]

On Wednesday, 30 April 2014 at 15:33:29 UTC, Andrei Alexandrescu 
wrote:
> 4. Currently, struct objects created with new do NOT have their 
> destructors called during collection. I think this may 
> continue, meaning that structs created with new are somewhat 
> low-level and are meant to be destroyed and deallocated 
> manually.
>
> 5. This brings up arrays of structs. As far as I understand, 
> destructors will never be called for these, even after all 
> references are gone:
>
> struct S { ~this() { ... } }
> auto a = new S[100];
>
> Unlike (4), arrays of structs are high-level and frequently 
> used. I think we must do something about it, so I plan to 
> support calling destructors for arrays of structs.

Although it would be a breaking change, I am intending to propose 
that the destructors of heap-allocated structs be handled in the 
same way as destructors of classes in my GC implementation. I am 
also intending to propose a guarantee that, if the program exits 
normally, all destructors will be invoked before the application 
ends. To help facilitate this I intend to have a thread dedicated 
to calling destructors. I'm still working on typing out the 
entire design of the GC, but I don't currently see a reason 
(design-wise) why I'd have to change these things.