Description
This is a duplicate of #8658. Linking any application that uses the OpenCV C API without optimizations now results in a undefined reference to cvRound. This is because this function is now defined ONLY in a C++-only header: fast_math.hpp.
The reply (by "alalek") on that bug was that the C API shouldn't be used anymore. I don't know who alalek is; is this the official position? This issue effectively kills the C API. I.e. it's no longer an OPTION to use the C API without experiencing pain. And this particular issue isn't even hard to fix. I can give you a patch, and we can agree to at least not kill the C API on purpose, yes?