I want to use Eclipse CDT to search for all occurrences of regular expresion, say foo(_bar_)*baz - in the bodies/bodies and declarations of functions/methods meeting a certain criterion. For the example let's make it all functions/methods named ignore_me (but within all classes and namespaces).
Is that possible somehow?
I'm not aware of a way to do this sort of search in Eclipse CDT.
Clang's AST matchers provide a rich domain-specific language for expressing queries like yours (and many other kinds), but using them requires writing code (in a clang plugin or standalone clang-based tool). It may be relatively straightforward to write a simple tool that allows you to write a query and searches a codebase for matches. I'm not sure whether such a tool is already available.