I\'m looking for a (preferably open source) tool that, given a large body of C/C++ code, will generate a visual or maybe XML graph of dependencies between classes (C++) and/
I haven't used any open sources tools for this, but the Rhapsody UML tool does a good job of doing this. They used to give a 30 day free trial to anyone who asked, IBM just bought it so I don't know if they still do.
http://www-01.ibm.com/software/awdtools/rhapsody/
It will reverse C/C++/Java/Ada.