[ANNOUNCE] Next Generation build method

Greg Schafer gschafer at zip.com.au
Mon Dec 10 22:51:57 PST 2007

Ken Moffat wrote:

> On Tue, Dec 11, 2007 at 08:41:06AM +1100, Greg Schafer wrote:
>>  - when targeting x86_64, it doesn't matter whether the host is running
>>    32-bit or 64-bit kernel or userland or combination of both, it just
>>    works.
>  In best /. fashion, I haven't read the links yet, but you're saying
> it's ok to run 64-bit userspace on a 32-bit kernel ?  I've used
> linux32 to enforce a 32-bit personality, but I've never managed to
> get it to work in the other direction.

Um, no. That's not possible. It's still essentially a native build method
which means we *must* be native by the time we start building the pass2
toolchain after the temp Glibc ie:

[[ $DIY_TARGET == x86_64* && $(uname -m) == i?86 ]] &&
	{ echo build a 64-bit kernel and reboot into it!; exit 1; }

In other words, if starting from a 32-bit host, one must use the pass1
cross toolchain to cross compile a 64-bit kernel (easy peasy) and reboot
into it.

Sidenote: the soon-to-be-released 2.6.24 kernel has merged the
i386 and x86_64 arches ie: it's now just "x86" which makes creating a
compatible 64-bit .config a whole lot easier.

>  Greg, thanks for posting this.  I look forward to reading the
> references you've provided (and also to finally saying goodbye to
> the testsuites on the initial toolchain builds which I assume will
> go with a cross-compile).

Say what? Folks are still running testsuites in Ch 5? (checks current LFS)
Ughh, that's insane. Sensible folks stopped doing this years ago... it
should be ripped out entirely IMHO.

>  I thought you used to dislike bi-arch on x86_64 ? (/me likes both
> pure64 _and_ bi-arch, but not at the same time ;-)

Not dislike, rather, I just feel it can be a whole lot of bother for the
average build-from-source person. But having said that, a basic 64-bit
bi-arch setup with just a 32-bit Glibc (minus the 32-bit versions of every
other lib in sight) can be quite useful as a 64-bit system with the
ability to compile and run occasional 32-bit code. Then, one has the
option to go further with the 32-bit stuff if desired.


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