Which CPUTYPE in make.conf?

[Michael Powell]

C. P. Ghost wrote:

> On Sat, Apr 24, 2010 at 7:32 PM, Michael Powell <nightrecon at hotmail.com>
> wrote:
>> I think this matters more to third party ports software builds than it
>> does the system. I thought that large pieces of the kernel were designed
>> to not make much, if any, use the various SIMD extensions. Maybe this has
>> changed and I'm behind the times.
> 
> I wouldn't bother setting CPUTYPE at all. It's more trouble than it's
> worth.

Actually, I've been setting CPUTYPE for many years and have never had any 
trouble as a result. I've always used the form: CPUTYPE?= blah instead of 
CPUTYPE= without the question mark. 
 
> And you're right: for most ports and for the whole system, it doesn't
> really matter. If you have a very specific port that needs particular
> tuning, it has either already been tuned individually by the port
> maintainer, or you could apply more optimizations yourself (which would
> likely require a specially compiled tool chain, when -O<something> with
> the base gcc/binutils isn't enough).

I have also used CFLAGS= -O2 -pipe COPTFLAGS= -O2 -pipe. About the only 
place it will really make any difference is in some multimedia apps. And 
you're right that if needed the port maintainer has already taken care of 
this.
 
> Unless you have a very specific need, better leave CPUTYPE alone.

Thing is, any performance increase is only going to be very small. So small 
the difference can probably not be seen subjectively. I'll do it as long as 
it creates no problem; if any problem were to arise over this I'd kill it in 
a heartbeat and not fuss over it. It is a point of diminishing returns. 
 
[snip]
-Mike