I have Xcode 4.5.2 on Moutain Lion, and I have install the lastest "Command Line Tools" but when I tried to compile with g++ or clang++ (and the options -std=c++11 -stdlib=libc++) I get an error. With g++:

cc1plus: error: unrecognized command line option "-std=c++11"
cc1plus: error: unrecognized command line option "-stdlib=libc++"

With clang++: 

clang: error: invalid deployment target for -stdlib=libc++ (requires OS X 10.7 or later)

It's in a Qt project.

So how can I used the C++11 on my Mac ?

c++ xcode c++11 g++ clang
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