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Clang

FAQ

Ref. By default, clang++ will not enable the C++11 features - you have to pass an additional flag during compilation. clang++ -std=c++11 [input files...] Or # enables some additional C++11 extensions GCC has clang++ -std=gnu++11 [input files...] Additionally, you can switch between using libstdc++ and Clang's own libc++, which are different implementations of the C++ standard library. libc++ in some cases might have a better implementation of the C++11 standard than your existing libstdc++ library.

# uses clang's C++ library in C++98 mode
clang++ -stdlib=libc++ [input] # uses clang's C++ library

# uses clang's C++ library and enables C++11 mode
clang++ -stdlib=libc++ -std=c++11 [input]
The latter is important if you're using Clang in an environment with an outdated version of libstdc++ (like Mac OSX), but note that the two C++ libraries are not compatible with each other, so you would have to rebuild any dependencies against libc++ if you were to use that.