title: iOS 6.0 Apple LLVM Compiler 4.1 error
body: <p>Updated Xcode to latest version and now getting a strange compiler error when I try to compile my existing project. I assume this is some build setting which needs changing but can't work out where.</p>
  
  <pre><code>Apple LLVM Compiler 4.1 error
  clang: error: the clang compiler does not support '-fobjc-abi-version=0'
  Command /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang failed with exit code 1
  </code></pre>
  
  <p>What does this mean?</p>