Hi, John, On Wed, Feb 3, 2010 at 6:32 AM, John (Eljay) Love-Jensen <eljay@xxxxxxxxx> wrote: > Hi Yue, > > You can get a list of toggle-able optimization flags like this: > > touch Empty.cpp > gcc -O2 -fverbose-asm -S Empty.cpp -o O2.s > gcc -O3 -fverbose-asm -S Empty.cpp -o O3.s > > However, that will not tell you what non-toggle-able optimizations are enabled, since -O2 enables many optimizations that are not controlled by command line flags. And -O3 enables a few more, as I understand it. > This is interesting, and works. > Nor will that tell you what optimization(s) were applied to a particular code segment. > Ok, then that's fine. Thank you very much! Yue
