Imported Upstream version 4.2.1.36

Former-commit-id: fb75898888a02f4d3a74cf0a5b841681bc4c7fa8

mcs/errors/cs0165-54.cs

@@ -0,0 +1,25 @@
+// CS0165: Use of unassigned local variable `res'
+// Line: 23
+
+class A
+{
+	public B b;
+}
+
+class B
+{
+	public void Foo (int arg)
+	{
+	}
+}
+
+class X
+{
+	public static void Main ()
+	{
+		A a = null;
+		int res;
+		a?.b.Foo(res = 3);
+		System.Console.WriteLine (res);
+	}
+}