(In reply to David Mandelin from comment #2)
> Did it just move to a different file?
No, it was rewritten as js::LifoAlloc.
The interface changes are straightforward, JS_ARENA_MARK => js::LifoAlloc::mark. For the JS_ARENA_ALLOCATE_CAST there's are ::new_ and ::alloc_ functions on the LifoAlloc.
(In reply to David Mandelin from comment #2)
> Did it just move to a different file?
No, it was rewritten as js::LifoAlloc.
The interface changes are straightforward, JS_ARENA_MARK => js::LifoAlloc: :mark. For the JS_ARENA_ ALLOCATE_ CAST there's are ::new_ and ::alloc_ functions on the LifoAlloc.