Unfortunately, the declaration above causes a slew of compiler errors (see below) that appear to be related to BasicBlock's copy constructor. Sure enough, I checked BasicBlock.h, and its copy constructor is declared private and is not even implemented. There appears to be some sort of design issue that prevents this class from having a copy constructor.

Is there some workaround for this on the Boost Graph side, or must vertex classes always have a copy constructor?

The "easy" workaround is to simply have the graph refer to BasicBlock by pointer instead of actually owning it. Pointers are definitely default and copy constructible :) Otherwise, those property classes are largely required to be copy and/or default constructible.

I might caution you about using directed_graph. It's built over adjacency_list<listS, listS, ...> so it might not be usable quite the same way that most of the documentation is listed.

Also, since I wrote the class, if you have any problems with it, please let me know so I can fix them!