Re: Why does C3 CPU downgrade in kernel 2.4.20?

[Dave Jones]

On Tue, Dec 10, 2002 at 12:02:25PM +0800, Joseph wrote:
 > Hi all,
 >   I rebuilt the 2.4.20 kernel with C3 CPU and found it been downgraded to
 > i486.
 >   And I check the file, linux/arch/i386/Makefile, in both of 2.4.19 and
 > 2.4.20 kernels.
 >   In 2.4.19, the CFLAGS adds "-march=i586".
 >   But in 2.4.20, the CFLAGS adds
 > "-march=i486 -malign-functions=0 -malign-jumps=0 -malign-loops=0".
 >   Why do this? Could anybody explain this to me?

I believe someone (Jeff Garzik?) benchmarked gcc code generation,
and the C3 executed code scheduled for a 486 faster than it did for
-m586
I'm not sure about the alignment flags. I've been meaning to look
into that myself...

        Dave