title: Something changed, now 5800 compiler errors from precompiled header
body: <p>I apparently changed something in an iPhone Xcode project, and now when it precompiles the headers I'm getting</p>
  
  <pre><code>In file included from [...] /Foundation.framework/Headers/Foundation.h:8,
                   from [...] /UIKit.framework/Headers/UIAccelerometer.h:8,
                   from [...] /UIKit.framework/Headers/UIKit.h:9:
  /Developer/Platforms/[...]/NSObjCRuntime.h:146: error: stray '@' in program
  /Developer/Platforms/[...]/NSObjCRuntime.h:146: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'NSString'
  </code></pre>
  
  <p>and then 5800 more errors...</p>
  
  <p>I'm hoping somebody else did this to themselves recently and can point me in the right direction!</p>