Hi,
I started using clang and libc++ for my projects and realized the need of working GDB pretty printers.
Version currently mentioned in documentation [1] is written in python2. I am using mostly debian and newer versions of gdb in repositories are linked against libpython3.4. Since debian is usually rather conservative I would expect other distributions to already use python3 as well.
I forked version converted to python3 (2to3), managed to fix issue with std::set and std::map printing and created basic documentation.
Help yourself:
https://github.com/koja/libcxx-pretty-printers
Regards
Jan Korous
[1] http://libcxx.llvm.org/docs/UsingLibcxx.html#gdb-pretty-printers-for-libc