Compiler Warning (level 2) CS0436

https://docs.microsoft.com/en-us/dotnet/csharp/misc/cs0436

// CS0436_a.cs
// compile with: /target:library
public class A {
   public void Test() {
      System.Console.WriteLine("CS0436_a");
   }
}  

The following example generates CS0436.

// CS0436_b.cs
// compile with: /reference:CS0436_a.dll
// CS0436 expected
public class A {
   public void Test() {
      System.Console.WriteLine("CS0436_b");
   }
}  

public class Test
{
   public static void Main()
   {
      A x = new A();
      x.Test();
   }
}