Change x86 default arch for 4.5?

[Joe Buck]

On Thu, Feb 18, 2010 at 02:09:14PM -0800, Jason Merrill wrote:
> I periodically get bitten by bug 34115: a compiler configured without 
> --with-arch on i686-pc-linux-gnu doesn't support atomics.  I think we 
> would only need to bump the default to i486 to get atomic support.  Can 
> we reconsider the default for 4.5?

Is anyone still manufacturing x86 CPUs that don't support the atomic
instructions?