On 13-10-2012 21:24, David Nadlinger wrote:
On Saturday, 13 October 2012 at 18:58:27 UTC, Alex Rønne Petersen wrote:
This is kind of terrible because adding the chunk of memory as a root
forces the GC to actually scan it, which is unnecessary when what you
really want is to pin the object in place and tell the GC "I know what
I'm doing, don't touch this".
If pointers in pinned objects make their targets live, there would be no
difference to simply adding the object as a root. So in your proposal,
pinned objects are implicitly marked live if they aren't reachable from
any of the roots, but any other objects reachable only from a pinned
object but not from a root would be collected – correct?
David
There is a difference: Adding the object itself as a root does not
actually guarantee that the object *itself* might not be collected. At
least, this is how I have to assume things work given that this is not
guaranteed here: http://dlang.org/phobos/core_memory.html#addRoot
As for your question: Not quite. A pinned object that points to any
other unpinned objects will implicitly keep those alive. This is at
least how I would expect it to work, following the principle of least
surprise.
--
Alex Rønne Petersen
[email protected]
http://lycus.org
