A simple case of bound checks skipped with ref and Unsafe.Add

BoundChecks.cs

using System;
using System.Runtime.CompilerServices;

public class C 
{
    public static void A(Span<int> a)
    {
        a[0] = 1;
        a[1] = 2;
        a[2] = 3;
    }
    
    public static void A(ref int a)
    {
        a = 1;
        Unsafe.Add(ref a, 1) = 2;
        Unsafe.Add(ref a, 2) = 3;
    }
}