FreeBSD 6

Nikolas Britton nikolas.britton at
Wed Jul 27 00:16:06 GMT 2005

On 7/26/05, Kövesdán Gábor <gabor.kovesdan at> wrote:
> Nikolas Britton wrote:
> >Is it just me or is -O2 now the default for kernel builds? What about
> >-Os, safe to use?
> >
> >
> >
> So is it for me. But if I specify some CFLAGS, for example -O3
> -march=athlon64, the
> building fails, but CFLAGS mustn't affect the kernel compiling process
> afaik. There is
> COPTFLAGS for that reason. I've also made a PR about this new, unwanted
> behaviour,
> but haven't got any answers so yet.

You are right, COPTCLAGS is for the kernel only. -O3 is not officially
supported for CFLAGS or COPTFLAGS. If you use -O3 for CFLAGS it will
break some ports. Also from my experience using anything higher then
CPUTYPE=p2 will break ports (like gstreamer).

This is what I normally add to my make.conf file:
CFLAGS= -Os -pipes
COPTFLAGS= -Os -pipes
#CXXFLAGS= don't remember what I set this too, don't use it a lot.

If I want a port to build with different settings I just tell it to
inline... make CPUTYPE=p4 install clean etc.

As far as -O2 as the default for the kernel... I thought it was more
important to have a small kernel then a faster but fatter one. The
smaller the kernel the more you can put in L1,2, and 3 cache and the
smaller the program the less it needs to hit ram, swap, and hard disk?
isn't this what apple does with their OS-X builds?

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