On Friday, 31 May 2013 at 17:14:52 UTC, Jonathan M Davis wrote:
On Friday, May 31, 2013 18:31:38 Carl Sturtivant wrote:
"The D Programming Language" (TDPL) p.178 asserts the
following.
"The objects themselves stay put, that is their locations in
memory never change after creation."
I take this to mean that the D garbage collector doesn't move
live objects and adjust all references to them the way that
some
garbage collectors do. That is to say, the addresses of objects
are not changed by the garbage collector.
Does D guarantee this?
I don't believe that there is any such guarantee in the
language. Structs on
the heap get moved around all the time, so having objects with
references to
themselves is effectively disallowed. The GC does not currently
ever move any
objects, but I don't believe that the language itself
guarantees that it never
will. It may be that in the future it would, though it's
unlikely given some
of the technical difficulties caused by having unmanaged
pointers and void* and
whatnot. Languages which run in a VM and are restricted to
managed pointers
are able to make many more assumptions than D is, making it
much easier for
them to do moveable garbage collectors.
- Jonathan M Davis
I assume you mean structs on the stack rather than on the heap -
structs on the heap are never moved currently.
