Test overriding from a secondary base for Itanium

Fixes https://github.com/mono/CppSharp/issues/1364.

Signed-off-by: Dimitar Dobrev <dpldobrev@protonmail.com>

tests/CSharp/CSharp.Tests.cs

@@ -102,6 +102,24 @@ public unsafe class CSharpTests : GeneratorTestFixture
 #pragma warning restore 0219
     }
 
+    private class OverriddenInManaged : Baz
+    {
+        public override int Type => 10;
+    }
+
+    [Test]
+    public void TestDer()
+    {
+        using (var der = new OverriddenInManaged())
+        {
+            using (var hasDer = new HasOverriddenInManaged())
+            {
+                hasDer.SetOverriddenInManaged(der);
+                Assert.That(hasDer.CallOverriddenInManaged(), Is.EqualTo(10));
+            }
+        }
+    }
+
     [Test]
     public void TestReturnCharPointer()
     {

tests/CSharp/CSharp.cpp

@@ -329,6 +329,11 @@ void Baz::setMethod(ProtectedNestedEnum value)
 {
 }
 
+int Baz::type() const
+{
+    return -1;
+}
+
 AbstractProprietor::~AbstractProprietor()
 {
 }
@@ -865,6 +870,24 @@ AbstractWithProperty::~AbstractWithProperty()
 {
 }
 
+HasOverriddenInManaged::HasOverriddenInManaged()
+{
+}
+
+HasOverriddenInManaged::~HasOverriddenInManaged()
+{
+}
+
+void HasOverriddenInManaged::setOverriddenInManaged(Baz* value)
+{
+    overriddenInManaged = value;
+}
+
+int HasOverriddenInManaged::callOverriddenInManaged()
+{
+    return overriddenInManaged->type();
+}
+
 IgnoredType PropertyWithIgnoredType::ignoredType()
 {
     return _ignoredType;

tests/CSharp/CSharp.h

@@ -161,6 +161,7 @@ public:
     int takesQux(const Qux& qux);
     Qux returnQux();
     void setMethod(ProtectedNestedEnum value);
+    int type() const override;
 
     typedef bool (*FunctionTypedef)(const void *);
     FunctionTypedef functionTypedef;
@@ -537,6 +538,17 @@ class DLL_API IgnoredTypeInheritingNonIgnoredWithNoEmptyCtor : public P
 {
 };
 
+class DLL_API HasOverriddenInManaged
+{
+public:
+    HasOverriddenInManaged();
+    ~HasOverriddenInManaged();
+    void setOverriddenInManaged(Baz *value);
+    int callOverriddenInManaged();
+private:
+    Baz* overriddenInManaged = 0;
+};
+
 class DLL_API PropertyWithIgnoredType
 {
 public: