games-emulation/mame2003-libretro
MAME (0.78) for libretro.
USE Flags
custom-cflags
Global: Build with user-specified CFLAGS (unsupported)
debug
Global: Enable extra debug codepaths, like asserts and extra output. If you want to get meaningful backtraces see http://www.gentoo.org/proj/en/qa/backtraces.xml