Re: how to enable -m64 on x86-linux for building ATLAS

[Matthew Woehlke <mw_triad@users.sourceforge.net>]

Dennis Wassel wrote:
> Fine. I'm now going to try to build a 64-bit glibc (and worry where to
> put it later, because I'm not root), and possible the full-fledged
> binutils toolchain and so on, but now I feel this
> chicken-and-egg-problem creeping up to me - wouldn't I need 64-bit
> support in my compiler to create the corresponding glibc?
> 
> D'oh!
> 
> Any pointers, docs or howtos anyone? Much appreciated!

It sounds like you want to look into how to build a cross-compiler. I've 
never attempted to do so, but surely there is documentation on how to 
bootstrap a cross compiler targeting a clean environment.

(As far a binutils, since you want cross-binutils, you are building 
32-bit binaries - i.e. your existing compiler is fine - that will 
generate 64-bit binaries. I'm not sure about libc, I guess it must be 
possible to build a "bare metal" cross compiler that you can use to 
build a libc; maybe you have to build a bare metal cross compiler first 
and then a cross compiler that uses that libc.)

Apologies for the not-very-helpful answer, but maybe this will at least 
point you in the right direction to go looking for further information.

-- 
Matthew
I don't see what C++ has to do with keeping people from shooting 
themselves in the foot.  C++ will happily load the gun, offer you a 
drink to steady your nerves, and help you aim. -- Peter da Silva (from 
cluefire.net)