Ruby shared_ptr fixes for use with minherit

Examples/test-suite/ruby_minherit_shared_ptr.i

@@ -0,0 +1,39 @@
+// Test ruby_minherit (multiple inheritance support) and shared_ptr
+%module(ruby_minherit="1") ruby_minherit_shared_ptr
+
+%include <boost_shared_ptr.i>
+%shared_ptr(Interface1)
+%shared_ptr(Base1)
+%shared_ptr(MultiDerived)
+
+%inline %{
+#include <boost/shared_ptr.hpp>
+class Interface1 {
+public:
+  virtual int Interface1Func() const = 0;
+};
+
+class Base1 {
+  int val;
+public:
+  Base1(int a = 0) : val(a) {}
+  virtual int Base1Func() const { return val; }
+};
+
+class MultiDerived : public Base1, public Interface1 {
+  int multi;
+public:
+  MultiDerived(int v1, int v2) : Base1(v1), multi(v2) {}
+  virtual int Interface1Func() const { return multi; }
+};
+
+int BaseCheck(const Base1& b) {
+    return b.Base1Func();
+}
+int InterfaceCheck(const Interface1& i) {
+    return i.Interface1Func();
+}
+int DerivedCheck(const MultiDerived& m) {
+    return m.Interface1Func() + m.Base1Func();
+}
+%}