How to reproduce:

1. Open attached project
- Project contains a single script:

using System;

public interface IMyInterface<T>
{
void OnNext(T value);
}

public static class Test
{
public static void Error<T>(IMyInterface<T> mi)
{
var act = new Action<T>(mi.OnNext); // il2cpp error
UnityEngine.Debug.Log(act);
}
}

2. Build to iOS
- Note the errors when building