Andy Piper <andy(a)xemacs.org&gt; writes: The big question is.. how? In December I tried doing the memcmp-ing thing.. I was so convinced it was the right idea that I even did it the clean way (i.e. make substructures that identify the part that can be memcmp'ed like Ben proposed) and spend a whole night doing the grepping and the replacing. Then the final compile. Indeed compare_runes was now (almost) a simple inlined memcmp... the result.. 15% SLOWER redisplay :-(. I still haven't figured out what went wrong. Jan P.S. If anybody want I can try and dig up the patch.