Said it before, I'll say it again: I build MAME on 10.6.8 "Snow Leopard" any time I want using Clang 3.7 and libc++ from MacPorts. If you're building with GCC on OSX, you're pretty much unsupported at this point.
Then instructions to install and build with the necessary clang version should be stickied instead of this, or in addition.
