byuu says:

Changelog:

  - moved to GCC 8.2 and C++17
  - fixed compilation under FreeBSD 12.0
  - don't read beyond the file size in
    SuperFamicom::Cartridge::loadMemory
  - add missing I/O cycle HuC6280::instructionImmediate
  - serialize Mega Drive's Game Genie state
  - serialize SPC7110::Thread information
  - enable 30-bit color depth support under the GLX/OpenGL 2.0 driver
    (doesn't work with OpenGL 3.2 yet)

The 30-bit color depth option isn't super useful, but why not? I need to
update ruby to detect that the display is actually capable of it before
exposing an option that can result in the driver failing to initialize,
however.