title: How to define g++ or clang++ in xcode 4?
body: <p>How do I use a c++ compiler (g++ or clang++) to compile a simple c++ project in xCode 4?</p>
  
  <p>You can assume I am in the project, in the Build Settings.
  I have in Build Options -> Compiler for C/C++/Objective-C -> Apple LLVM compiler 3.0 and LLVM GCC 4.2 as options.<br>
  Is either one appropriate or do I have to install another one?<br>
  How do I do that?</p>