I'd still like to be able to have something sorted in the binary, but I guess without conste traits that can run very late in code gen it would be difficult. And there is also the parallel backend when codegen units isn't 1.
It would open up a lot of interesting possibilities if it could be done.
Now a question that rises is why @dtolnay did not use linkme for typetag but rather a actor solution. Is the ctor solution more powerful inherently? What are we missing out on by forgoing it?