Precise GC state

[Dmitry Olshansky]

On Sunday, 26 November 2017 at 04:01:31 UTC, jmh530 wrote:
> On Friday, 24 November 2017 at 05:53:37 UTC, Dmitry Olshansky 
> wrote:
>> A better GC is a great direction. Generational one is not 
>> feasible unless we disallow quite a few of our features.
>
> What about @safe?

If all of the code is 100% @safe (not system and not trusted) you 
have a different language where write barriers would be cheaper 
to implement.

Sadly you can’t “skip” write barriers in your @system code 
because it may run as part of larger @safe. Which is where they 
are the most costly.