Q: Compiles for wrong processor and it still worked

[Dan Nelson]

In the last episode (Sep 28), Alex de Kruijff said:
> I have compiles my world sources for the PIII processors. I have
> recently discoverd that i have a number of PII processors. The compiled
> code for PIII still works on them. I'm ammazed. :o Can anybody explain why?
> 
> I include this in to /etc/make.conf

686, pII, p3, and p4 are all basically the same instruction set.  the
later versions add more MMX and SEE operations, and I don't believe gcc
generates code that uses them.  The different arch flags probably just
change the instruction timing tables.

-- 
	Dan Nelson
	dnelson at allantgroup.com