Forgot to offset derived type's gchandle offset

src/Mono.Cxxi/CppTypeInfo.cs

@@ -177,13 +177,16 @@ namespace Mono.Cxxi {
 				baseType = baseType.Clone ();
 				baseType.IsPrimaryBase = false;
 
-				baseType.gchandle_offset_delta += native_size_without_padding + CountBases (b => !b.IsPrimaryBase) * IntPtr.Size;
+				// offset all previously added bases
-				baseType.vt_overrides = baseType.vt_overrides.Clone (); // managed override tramps will be regenerated with correct gchandle offset
-
-				// now, offset all previously added bases
 				foreach (var previousBase in base_classes) {
 					previousBase.gchandle_offset_delta += baseType.NativeSize;
 				}
+
+				// offset derived (this) type's gchandle
+				gchandle_offset_delta += baseType.GCHandleOffset;
+
+				baseType.gchandle_offset_delta += native_size_without_padding + CountBases (b => !b.IsPrimaryBase) * IntPtr.Size;
+				baseType.vt_overrides = baseType.vt_overrides.Clone (); // managed override tramps will be regenerated with correct gchandle offset
 			}
 
 			base_classes.Add (baseType);

tests/InheritanceTests.cs

@@ -112,6 +112,12 @@ namespace Tests {
 			{
 			}
 
+			public override int Number {
+				get {
+					return 25;
+				}
+			}
+
 			// override virtual member inherited from non-primary base
 			protected override void MultiplierClass__Multiply (int n)
 			{
@@ -123,12 +129,12 @@ namespace Tests {
 		public void TestManagedOverride2 ()
 		{
 			var cls = new ManagedOverride2 ();
+			Assert.AreEqual (-25, cls.NegativeNumber, "#1");
 			cls.MultiplierClass.Multiply (7);
-			Assert.AreEqual (5, cls.Number, "#1");
+			Assert.AreEqual (30, ((MultiplierClass)cls).Number, "#3");
-			Assert.AreEqual (30, ((MultiplierClass)cls).Number, "#2");
 			cls.CallMultiply (2);
-			Assert.AreEqual (5, cls.Number, "#3");
+			Assert.AreEqual (25, cls.Number, "#2");
-			Assert.AreEqual (300, ((MultiplierClass)cls).Number, "#4");
+			Assert.AreEqual (300, ((MultiplierClass)cls).Number, "#5");
 		}
 
 		[Test]