I wanted to compile a C++11 example on OS X 10.8.5 but it took me a while to figure out how.  Using good old g++ with the -std=c++11 option will not work like it does on Linux since g++ is only a symlink to llvm-g++-4.2 on OS X 10.8. Apparently the Gnu compiler is no longer installed due to license issues.  What works is to use clang++, the new(ish) front-end to Apples llvm compiler and for some reason that you have to tell clang++ which C++ standard library to use. For now I'm to lazy to investigate why that is but the following compiled the C++11 example code on cplusplus.com:

clang++ -std=c++11 -stdlib=libc++ cpp11example.cpp -o cpp11example

... or you can download the Gnu compiler and install it but for a few example code that seemed like overkill.