Recosystem package in R - C++ setup on Mac

Recosystem is a wrapper of LIBMF in R, thus "needs a C++ compiler that supports C++11 standard" and "It is strongly suggested to set proper flags according to your type of CPU before compiling the package" as described here.

I don't have much knowledge about C++, and thus intimidated by these statement... As a Mac user I'm totally at loss what to do to set up the C++ environment needed for this package. Anyone have done this before? Any suggestion would be appreciated. Thanks!