On 1/12/2014 2:40 AM, Benjamin Thaut wrote:
Am 12.01.2014 11:27, schrieb Rainer Schuetze:
I think a moving collector is currently not feasible without restricting
the language a lot, probably similar to safe D and more. I'm not sure we
want that in general.
Could you give an example which part of the language would not be doable with a
moving collector? The only thing that comes to my mind is unions and that
problem can be solved by allowing the user to specify manual scanning functions
for structs or classes containing unions.
Also I don't think that we can create a GC which performs as good as the one of
Java or C# if we are not willing to make the neccessary changes for a moving gc.
A moving GC is already supported by D's semantics.
Unions are dealt with by 'pinning' those objects, i.e. simply don't move them. I
know this can work because I implemented a mostly copying generational collector
years ago for Java. (After I invented this, someone else came out with a paper
about a "mostly copying" collector, so I didn't get any credit. Oh well! But the
idea is sound and it works in the real world.)
