So I made
Box be treated like
&mut, exploiting that it is a lang item. That gives us some nice extra guarantees. However, how I am having trouble with
Box::into_unique... I somehow need to erase the tag and trigger and
EscapeToRaw, and that is not trivial :/ I mean I could always use
transmute, but that does not seem nice.
Cc @nikomatsakis @Gankro
Ah, I found a way
actually... I don't even want barriers for boxes. then things pass without that PR, though I have to make sure I understand why.