Our DMS Software Reengineering Toolkit with its C front end and C++ Front End can provide a lot of information about C and C++ programs.
DMS with the C front end can parse large sets of C source files, build complete ASTs (even capturing comments) and symbol tables, and provide control and data flow analysis, with points-to analysis and call graphs. The C++ front end builds ASTs and full symbol tables, but does not yet provide all the flow analysis information.
DMS provides facilities to invoke the parsers/flow analyzers; you provide some custom code to extract the information you want.
It has the additional capability of modifying the ASTs and regenerating compilable source code.
I think you'll find that no tools for which you can extract precise custom data are "easy" to use; the very nature of the questions you ask and the answers have lots of complications caused by the complex language semantics.
