Hi, I ran some benchmarks using g++ V3.3.1. Two functions are called from a main program. While both doing exactly the same array manipulation (dot product on doubles), one of the functions uses the __restrict keyword to tell the compiler that pointer aliasing is "turned off" in that function. To my surprise, the __restrict version is not faster than the conventional one. In fact, they show the same speed. Do I have to specify any compilation option to tell g++ to really take advantage from the __restrict information? Didn't find anything in the docs however. I tried using -o, -o2, -o3, giving always equal speed for both functions. Regards Kaspar -- GMX Weihnachts-Special: Seychellen-Traumreise zu gewinnen! Rentier entlaufen. Finden Sie Rudolph! Als Belohnung winken tolle Preise. http://www.gmx.net/de/cgi/specialmail/ +++ GMX - die erste Adresse für Mail, Message, More! +++