title: Xcode 7 command failed due to signal: illegal instruction 4
body: <p>I just used Xcode 7's migration tool to migrate a project from Swift 1.2 to 2. After fixing up errors missed and such, all is well except for an error which prevents me from even building: Command failed due to signal: illegal instruction 4. </p>
  
  <p>I have tried the help in these articles (<a href="https://stackoverflow.com/questions/30816623/xcode-7-and-swift-2-0-command-failed-due-to-signal-abort-trap-6">Xcode 7 and Swift 2.0 : Command failed due to signal: Abort trap: 6</a>, and <a href="https://stackoverflow.com/questions/30724897/command-failed-due-to-signal-abort-trap-6">Command failed due to signal: Abort trap: 6</a>) which are not identical issues to mine, but nevertheless they were not able to fix the issue. </p>
  
  <p>I have cleaned the build and removed the derived data folder. I have up to date CocoaPods installation, Xcode tools are at 7.0, and I Swift compile optimization is at None. Is there anything else I'm missing? </p>
  
  <p>Thanks!</p>