 <p>As Igor says, Apple's fork of gas is ancient and wants:</p> <ul> <li>.global replaced by .globl</li> <li>all instructions in lowercase</li> <li>replace ';' comment separator with '@'</li> <li>stub labels for address imports</li> </ul> <p>I've written a pre-processor awk script for the Tremolo .s files to make them acceptable to Xcode, which I'll contribute back via Robin.</p> <p>Alternatively, you could try <a href="http://github.com/gabriel/ffmpeg-iphone-build/blob/master/gas-preprocessor.pl">this</a>.</p>