title: How do you set file-specific build settings in XCode 4?
body: <p>In xcode 3 it was possible to configure specific option for building every single file of a project, like for example disabling specific warnings, thumb code generation and so on.<br>
  In xcode 4 such feature is not available, or at least not in an intuitive way. This is however supported, at least as a backward compatibility feature, in projects imported from xcode 3.x.</p>
  
  <p>Does anyone knows a way to specify those settings without having to open the project back in older xcode or creating a project for every single file?</p>