> You should be able to use __attribute__ ((aligned (16))) to make this > happen. I knew that, it's just that I wanted to minimize cache pollution because my app thrashes cache badly. My bigger question is if stack is 16 byte aligned by default on modern 64 bit distributions? Thanks, -- Rohit Garg http://rpg-314.blogspot.com/ Senior Undergraduate Department of Physics Indian Institute of Technology Bombay