title: Device build fails after upgrading to Xcode 8
body: <p>Since upgrading to Xcode 8 I cannot run any app on my iPhone. The build fails with error:</p>
  
  <blockquote>
    <p>error: Task failed with exit 0 signal 11</p>
  </blockquote>
  
  <p>I can run the apps on the simulators, just not on a device.
  The full error message:</p>
  
  <blockquote>
    <p>error: Task failed with exit 0 signal 11 {   /usr/bin/codesign
    '--force' '--sign' '7F49C2A625C8976762BDEA351F8DA88E4F6FED22'
    '--verbose'
    '/Users/reshef/Library/Developer/Xcode/DerivedData/testXcode-eltpwhxdshmmlygolxcnsroevmoo/Build/Products/Debug-iphoneos/testXcode.app/Frameworks/libswiftCore.dylib'
    }</p>
  </blockquote>