Why -mtune=atom?

[drago01]

On Thu, Mar 12, 2015 at 2:02 PM, Florian Weimer <fweimer at redhat.com> wrote:
> The default CFLAGS set by RPM include “-mtune-atom”.
>
> Why?  I doubt Atom CPUs are Fedora's primary target.  It's not even a
> documented GCC option.  There is such a wide variety of CPUs under this
> label that it's not even clear what it would mean.

Well because at that time atoms where the only newly sold i686 hardware.