Unfortunately I can't. That's why I welcome the JetBrains announcement. Xcode doesn't even attempt to do the most basic things like renaming and code completion is entirely broken. Eclipse was too slow to be usable last time I checked and code completion didn't work properly either.
There is a relatively new clang based vim plugin that I haven't tried yet. Using clang to parse C++ into an AST is the right approach, so it sounds promising.