Grant wrote:
> 'man gcc' has greatly cleared this up for me. Would specifying
> -fomit-frame-pointer and -O2 or -O3 be redundant since it is included
> in either of those?
I recently discovered, that on x86 systems (like celeron or the
P3) -fomit-frame-pointer is *NOT* included when setting -Ox. If
required, you need to do that manually.
> -pipe isn't listed in that man page.
Dunno. I always use the online docs on
http://gcc.gnu.org/. > There is a warning about using -O2 "on programs that use computed
> gotos". Has anyone actually run into this problem and fixed it by
> specifying -O instead?
No. I'm running a O3 system with no problems-
> Is there a good rule of thumb to figure out which optimization setting
> to use on a particular system?
Don't go crazy on those CFLAGS. For sure, they have some influence, but
in the very most applications, you will not notice any difference at all
between -O3 and no -O. There are some exceptions where a difference is
*FEELABEL* (ssl, zlib I'd suppose), but those are rare. It's much more
important to have a "lean" system; ie. to have good USE flags.
Alexander Skwar
--
Quit worrying about your health. It'll go away.
-- Robert Orben
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