> because it is using the Boehm GC
For what reason? Mono has a pretty good precise GC since many years.
back
1 comments
Yes, SGen should be a lot better, but Unity cannot use it because they hold and pass raw pointers around everywhere. That's fine for Boehm but not possible with SGen. They're working on fixing this already but not sure why they aren't planning a move to a better GC.
Well, if they port to .NET (CoreCLR), that will move them to the MS GC.
Yes, but it also puts them in an awkward situation! They recommend (or even require, for some platforms) using IL2CPP for release builds which will still use Boehm GC and not run as quick as CoreCLR.
Do they still need IL2CPP if they have AOT? The goal was always to be able to have cross-platform native binaries right?
In theory yes, IL2CPP doesn't need to exist with modern .NET AOT support. In practice, per quotes in the article Unity may have a bit of a sunk cost issue and has no plans to support .NET AOT, only IL2CPP.
Some of that sunk cost may be the above mentioned pointer issue and not enough current plans for a smarter FFI interface between C++ and C#.
Unfortunately they do still need IL2CPP because Unity took a different direction than .NET: most reflection still works with IL2CPP but does not with .NET AOT. Switching would be a huge breaking change for everyone, including Unity.
Platform support is also still better with IL2CPP but .NET is catching up.