I am trying to profile a desktop OpenGL program with XCode. Neither instruments nor XCode's "capture GPU Frame" seem to be doing anything.
Are these features iOS only and just not labeled as such? If so, what are the options for profiling OSX OpenGL programs?
Yes, the Xcode "capture GPU frame" is only functional when running on iOS (at least, in Xcode 6.3 - perhaps this will be enabled in a future version). You can use the the OpenGL Profiler provided by Apple, which offers the similar functionality.