Cpp code in c

I hope I did this correctly. This is the first time I've tried this. I do get an error on make test:

Testing callback_test                                    0.000 [ ok ]
Testing behavior_testAssertion failed: (value > 0), function behavior_test, file function.c, line 1928.
*** [library_test] Signal 6

But so far the gem seems to work. I'll keep trying to track down the problem.