On 14 Apr 2020, at 23:41, Konstantin Osipov <kostja.osipov@gmail.com> wrote:

This is unrelated. 1.5 didn't have plugin api and no ffi exports
and mons was hacking into it.

In fact he wasn't hacking into functions at all, he was hacking
into global state, such as cord_ptr->fiber, and it was not (and I
believe is not) removed from the visibility list by linker.

In short:
When trying to understand how this "feature" worked before, look
at 1.5, not 1.6+.