[malkia]

I'm not an expert on the topic, but JIT is not allowed in certain places - like game consoles, ios, etc, to the point where even simpler trampoline (ffcall, libffi) are not allowed too. As such AOT helps there where JIT can't be used, but does not support absolutely everything (C# templates when comes to types that are not yet loaded I guess?).

[MichaelGG]

With C# generics on non-struct types, the emitted code is the same regardless of the type. On struct-types, it's necessarily different because there's no object header and the size of the objects can differ.

But, I can't think of a way to get an unknown struct type into a generic function without boxing (which makes it no longer a struct type). So for an AOT compiler it shouldn't be an issue. And there's probably some clever way to emit generic code for structs, too.

But generics have their own implementation difficulties and Mono didn't support them for a while in AOT.