[opticfluorine]

Not disagreeing with your point, but it couldn't be a compiler optimization, could it? The compiler isn't able to infer that the class will not be inherited anywhere else, since another compilation unit unknown to the class could inherit.

[vedantk]

Possibly not in the default c++ language mode, but check out -fwhole-program-vtables. It can be a useful option in cases where all relevant inheritance relationships are known at compile time.

https://reviews.llvm.org/D16821

[bluGill]

Which is good, but may not apply. I have an application where I can't do that because we support plugins and so a couple classes will get overridden outside of the compilation (this was in hindsight a bad decision, but too late to change now). Meanwhile most classes will never be overriden and so I use final to saw that. We are also a multi-repo project (which despite the hype I think is better for us than mono-repo), another reason why -f-whole-program-vtables would be difficult to use - but we could make it work with effort if it wasn't for the plugins.

[ftrobro]

I assume it could be or is part of link time optimization when compiling an application rather than a library?