title: Any ideas why I'm getting these errors in xcode?
body: <p>I have the following errors in xcode below, any ideas what's causing these?</p>
  
  <pre><code>arm-apple-darwin10-llvm-g++-4.2: /Users/&lt;foldername&gt;/Library/Developer/Xcode/DerivedData/Build/Products/Debug-iphoneos/libbtexternal.a: No such file or directory
  arm-apple-darwin10-llvm-g++-4.2: /Users/&lt;foldername&gt;/Library/Developer/Xcode/DerivedData/Build/Products/Debug-iphoneos/libbtexternal.a: No such file or directory
  lipo: can't figure out the architecture type of: /var/folders/1x/_btz9s41381cdzz41ty0r5fm0000gn/T//cc8KPWhc.out
  error: linking step of external dylib build failed, probably due to missing framework or library references - check the contents of the btexternal.ios file
  Command /bin/sh emitted errors but did not return a nonzero exit code to indicate failure
  </code></pre>