last changes from bloomberg.

cpp/shared_ptr_cast.cpp

@@ -0,0 +1,23 @@
+/* Check cf5-opt.vim defs.
+VIM: let b:lcppflags="-std=c++11 -O2 -pthread"
+*/
+
+#include <memory>
+
+class A 
+{
+    int i;
+};
+
+class B : public A
+{
+    int j;
+};
+
+int main()
+{
+    std::shared_ptr<A> a = std::make_shared<B>();
+
+    std::shared_ptr<B> b = std::static_pointer_cast<B>(a);
+}
+