Additional information: Failed to resolve type reference

I have a generic static class that has a method with an `in` parameter. It compiles in mono, but not il2cpp.

Method in question:

Code (CSharp):

1. public static void Send<T> ( in T message = default ( T ) ) where T : struct
2. {
3.             ...;
4. }

Are these code features supported in IL2CPP? Is there a workaround?

 

Might be related to the limitations in the Generic Virtual Methods section.
https://docs.unity3d.com/Manual/ScriptingRestrictions.html

 

Could be related, though the generics work without the `in` parameter.