Yeah, unfortunately the only correct way to do this is to use a debug build of Python. It isn't that difficult to build, but it is extra work and may not be an option at all depending on context (for example, some businesses won't let employees access source code to open-source projects).

If you link against python3.dll rather than python34.dll (there's a pre-processor variable to set, but I don't remember it off the top of my head) then you should avoid most of the debug/non-debug issues. I think you'll still need the #undef _DEBUG code though, and you'll lose access to some functionality, so it may not be an appropriate solution for you.

I don't think there's any good fix for this for 3.4, short of someone building and releasing a debug build from the same changeset as the actual release. For 3.5 I may be able to add an installer option to install debug binaries alongside the release ones. I'll put some thought into it and try some things out.