These are already in the tree in several places to protect (empty) post write barriers. We should get these methods tested on more compilers by exposing them while they are still empty.
Created attachment 586617 [details] [diff] [review] v1: trivial This is copied directly from JSGC_INCREMENTAL. Is it too early to expose the empty post barriers, or should I have done this last year, before I started?
Could you make this opt-in instead of opt-out? That is, copy the root analysis one rather than the incremental one?
Created attachment 593700 [details] [diff] [review] v2: opt-in