This is the mail archive of the
gcc-help@gcc.gnu.org
mailing list for the GCC project.
Re: gcc optimization option flags
M R Swami Reddy wrote:
> Hello Andrew,
> I used the -O1 and options listed with --verbose-asm separately, but the
> generated .s file differs. Did I miss some more options apart from the
> --verbose-asm listed?
>
> For ex:
> > gcc -O1 test.c -S -o test-o1.s
>
> > gcc test.c "option listed in .s file with -version" -S -o
> test-listopts.s
>
> test-o1.s and test-listopts.s are differs.
They do, and that's right. Unless you select -O you don't get any
optimizations, no matter what other flags you set.
Andrew.