Gambatte is a Nintendo Game Boy/Game Boy Color video game system emulator that can be used as a libretro core.
Gambatte is an accuracy-focused, open-source, cross-platform Game Boy Color emulator written in C++. It is based on hundreds of corner case hardware tests, as well as previous documentation and reverse engineering efforts.
To build the debugging symbols use: DEBUG=1 ./gambatte-libretro.SlackBuild