The title is a bit deceiving since it is what might be coming in C# 8.

Here is an interview with the PM of C# language development about what could be coming in C# 8.

https://channel9.msdn.com/Blogs/Seth-Juarez/A-Preview-of-C-8...

Not anything earth shattering, but interesting nonetheless.

I'd be interested in looking at the generated IL, especially for nullability info and default interface methods.

They're actually opening up the CLR and making changes to it now, so it's not all compiler tricks!

That's indeed true for the default interface implementation, but I believe for nullability it's just compiler warnings. At runtime, nothing will be left in the IL for this. It just isn't possible to do that and maintain backward compatibility