Hello! First post! Anyway, down to the problem.
I am creating a multiplatform (hopefully) plugin system, and was testing the strength/user friendlyness of it, when I wanted to try how it versions. I did this by adding a new abstract function to the app's copy of the interface. I ran it, without calling that new method, and all was well. The problem came when I added a call to that method, and as the plugin's interface did not define that method, I got a segfault/access violation.

My question is how can I test internally from the app if the plugin is sane (contains all members) or not? Or better yet, how can I test if a plugin contains any given member? I can supply code on request.