Re: Possibility of adding -march=native to x86

From: H. Peter Anvin
Date: Thu Oct 25 2007 - 18:04:54 EST


Adrian Bunk wrote:

Yes for something like a distro kernel it is bad but as I said before
this isn't what this is for.

Eventually it would be nice to to a make localkernel and for a
customised kernel to be build compiling in all pci / pci express
drivers into the kernel and all usb devices as modules.

Auto magically detecting the cpu would be part of that

I hate getting a new piece of kit and then have to figure out from
lspci which options need to be turned on and the the really iritation
part of finding the option in make menuconfig

What exactly is irritating?
Please name the problems so that they can be fixed.

Detecting the cpu and using march=native could be all part of that

You don't need march=native for this.

You have to set the right config option for your CPU and you automatically get the right compiler options.


There was a long discussion years ago -- the infamous "Aunt Tillie" thread -- about automatically configuring customized kernels for specific hardware.

It's somewhat of an unusual thing to bother with these days, except for people who develop and maintain the kernel.

-hpa
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