GC options

[Radu]

On Friday, 25 January 2019 at 13:33:25 UTC, Alex wrote:
> I'm experimenting with GC, and reading
> https://dlang.org/spec/garbage.html#gc_config
>
> There is an option setting possible via
> ´´´
> extern(C) __gshared string[] rt_options = [ "gcopt=gc:precise" 
> ];
> //gc:conservative|precise|manual
> ´´´
> conservative and manual seem to work, while setting gc to 
> precise, yields the error:
>
> "No GC was initialized, please recheck the name of the selected 
> GC ('precise')."
>
> Is the docu out of date, or do I something wrong?
> And another question: is there some extended docu, what do the 
> options lead to?

The precise collector was only recently added 
https://github.com/dlang/druntime/pull/2418