Destructors and Deterministic Memory Management

[Sean Kelly]

Georg Wrede wrote:
> 
> Dsimcha wrote "Since the destructor called by the GC can't reference 
> sub-objects", I got into thinking that we'd then need a myDestructor.
> 
> But
> 
>    delete myobject;
> 
> calls ~this() in myobject, as does the GC, as does program exit.
> 
> I also tested, and the referenced other objects did get deleted. No 
> problem. That implies releasing other resources works, by simply having 
> such release code in ~this() for the object.
> 
> I found no difference in calling delete or letting the GC do it. So, 
> originally dsimcha's problem was imagined?

If an object might possibly be finalized by the GC rather than deleted 
explicitly then its dtor can't referfence subobjects (because the GC 
doesn't guarantee any particular finalization order).  These subobjects 
will be finalized by the GC anyway when it detects that they're no 
longer referenced, but sometimes it's nice to do something with these 
objects when you know they're still valid.  My example provided a way 
for a different routine to be called for deterministic vs. 
non-deterministic finalization to allow for this.