Imported Upstream version 5.10.0.78

Former-commit-id: 46737382176d7b811604042c613d5df6eef74f33

mcs/tests/test-ref-10.cs

@@ -0,0 +1,24 @@
+// Compiler options: -langversion:latest
+
+using System;
+
+ref struct ValueStringBuilder
+{
+	public override string ToString ()
+	{
+		return "aaa";
+	}
+}
+
+
+class X
+{
+	public static int Main ()
+	{
+		var s = new ValueStringBuilder ();
+		if (s.ToString () != "aaa")
+			return 1;
+
+		return 0;
+	}
+}