Should we have primitive fill-once variables?

David Feuer david at
Fri Jun 29 18:22:38 UTC 2018

On Friday, June 29, 2018 2:13:39 PM EDT Joachim Breitner wrote:

> I don’t know! Maybe the GC can treat a filled IVar differently (because
> it is no longer mutable?) But really, I don't know :-)

That's a very good point. If we turn the IVar into a pure value, then it loses its "dirty" bit and the GC no longer has to check whether it's pointing to a newer generation. But this is getting into territory that's pretty murky to me.

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