Imported Upstream version 3.6.0

Former-commit-id: da6be194a6b1221998fc28233f2503bd61dd9d14

mcs/tests/test-298.cs

@@ -0,0 +1,50 @@
+using System;
+
+class A
+{
+	public static int operator + (short x, A b)
+	{
+		return -1;
+	}
+	
+	public static int operator - (A a)
+	{
+		return -1;
+	}
+}
+
+class B : A
+{
+	public static int operator + (int x, B d)
+	{
+		return 1;
+	}
+	
+	public static int operator - (B b)
+	{
+		return 1;
+	}
+}
+
+class C : B
+{
+}
+
+public class Test
+{
+	public static int Main ()
+	{
+		var b = new B ();
+		short s = 3;
+		var res = s + b;
+
+		if (res != 1)
+			return 1;
+		
+		var c = new C ();
+		if (-c != 1)
+			return 2;
+
+		return 0;
+	}
+}