Hi, What is the default stack alignment for gcc 4.4 on x86-64 linux? I assume it is 16 bytes so that SSE can use aligned loads and stores. I have googled for it a little and found some references for it that say so in passing, but I'd prefer to get some official blessing for it. My real issue is that I would like to declare certain variables on stack as aligned on 16 byte boundaries, so I can load/store them quickly. Of course, I'd prefer if this didn't involve _any_ overhead. http://gcc.gnu.org/onlinedocs/gcc/i386-and-x86_002d64-Options.html This here says that stack can be aligned to 16 bytes, which is also default. If I wish to avoid any code size increase, is there any particular order of declaring these variables which I should follow so that no extra space is consumed for padding. I would have thought that GCC would be smart enough to reorder variables to minimize code bloat, but..... I am using fedora 11, so all code is compiled using gcc 4.4. Not sure what the compilation options are. Thanks, -- Rohit Garg http://rpg-314.blogspot.com/ Senior Undergraduate Department of Physics Indian Institute of Technology Bombay
