Jude, the initial CFLAGS I suggested are safe, but suboptimal.  They do not 
tune your system's compiler to utilise all of your CPU's instructions.

In the first instance, you should set the CFLAGS as appropriate for your PC 
and specifically include -march=native, as suggested by Waldo.  Please check 
this chapter in the Gentoo Handbook:

https://wiki.gentoo.org/wiki/Handbook:AMD64/Installation/
Stage#Configuring_compile_options

Also, add the appropriate CPU USE flags either in CPU_FLAGS_X86="..." in your 
/etc/portage/make.conf, or in /etc/portage/package.use/00cpuflags.  You can 
install and run cpuid2cpuflags to print out your CPU's USE flags - e.g.:

mkdir /etc/portage/package.use   # if not set up yet
echo "*/* $(cpuid2cpuflags)" > /etc/portage/package.use/00cpuflags

Then you can proceed with the steps in the Handbook to install your system.

The download of binary packages is a more recent choice offered by Gentoo and 
can save time as opposed to compiling everything from source on your system.  
Previously posted links explain how to configure your system to set up and use 
a gentoo binhost.

If there is a /binpackages/ subdirectory on the mirror it will contain the 
precompiled binary packages and given you are running a modern CPU, you should 
set /x86-64-v3 in your binrepos.conf.

HTH.

On Friday, 24 May 2024 13:29:46 BST Jude DaShiell wrote:
> Michael,
> 
> The changes you selected worked.  I got mirrorselect compiled and ran it
> and got http ftp and rsync repos defined.  I'm wondering have all of the
> gentoo mirrors got binaries?
> 
> 
> --
>  Jude <jdashiel at panix dot com>
>  "There are four boxes to be used in defense of liberty:
>  soap, ballot, jury, and ammo.
>  Please use in that order."
>  Ed Howdershelt 1940.
> 
> On Fri, 24 May 2024, Michael wrote:
> > On Friday, 24 May 2024 09:57:36 BST Waldo Lemmer wrote:
> > > Hi Michael,
> > > 
> > > -march=x86-64 and -mtune=generic will not speed up your OS installation.
> > > These flags tell compilers to produce binaries that can run on any AMD64
> > > system and that aren't optimized for your specific system.
> > > 
> > > These flags have no effect on binary packages, since those have already
> > > been compiled.
> > 
> > You're right, those are the settings the binary packages have been built
> > with - my mistake, sorry!
> > 
> > The CFLAGS on the client should/could be tuned to its own CPU with "-
> > march=native". The "... speeding up of the OS installation" I had
> > mentioned
> > referred to downloading the binaries, rather than having to build them
> > locally.
> > 
> > Anyway, the CFLAGS Jude posted are incorrect:
> > 
> > CFLAGS="-O2 -pipe -native"
> > 
> > and his CPU_FLAGS_X86 are incomplete:
> > 
> > CPU_FLAGS_X86="mmx mmxext sse sse2"
> > 
> > Your links should hopefully help Jude to set the correct settings for this
> > system, before he continues with the Gentoo Handbook.

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