586 kernels.

[Alan Cox]

On Wed, Jun 20, 2007 at 04:03:21PM -0400, Bill Nottingham wrote:
> Dave Jones (davej at redhat.com) said: 
> > Yeah. The alternative is that I un-kill 586, and we continue shipping
> > that forever.  (Or we just tell those 38 586 users to go make their
> > own spin).
> 
> Patch RPM. :P

The history might be good here actually as I guess Bill is one of the few
folks at Red Hat long enough to remember it

gcc produced "686" code that wasn't in fact 686 machine architecture compliant

The gcc team denied this until I quoted them pages from the Intel doc (ok
obscure pages but they are there)

It was decided by the gcc folks that it was better to keep gcc 686 including
cmov and tell people to use 586 otherwise (there were good performance reasons
on original PPro when the decision was made but not by PIV)

A hack was put into rpm to say 686 is "686 + cmov"

It was agreed that rpm needed fixing properly anyway for architecture - notably
that architectures should become dependancies anyway as should cpu flags. That
somehow never happened

(The reasoning being that a PC would intrinsically supply "686" "686_cmov" etc
while a PPC would not, but qemu on ppc could provide "686" and allow 686
binaries to be installed and stuff. It's actually not as bright as it sounds
when you think about multiarch, in fact in some ways we should probably be
glad it didn't happen ;) )

Anyway fix gcc and you can fix rpm and you get back to the world as intended