Multithreading issues with C++ support?

[David Nolden]

Yep exactly these issues make multi-threaded parsing crash on real multi-core 
machines.

We need to somehow get the languagesForUrl(..) function thread-safe, that's 
the core problem.

A simple and fast workaround would be caching the list returned by 
languagesForUrl by the file-extension, but it would only make the crash much 
less probably, not completely impossible.

The problem is, if kdelibs 4.2 is not threadsafe in this regard, then we will 
have to work around it, since we want to run on that version.