Re: [gentoo-user] Will a 64-bit-no-multilib machine cross-compile 32-bit code?

[Mike Gilbert <floppym@gentoo.org>]

On Mon, Mar 23, 2015 at 9:51 PM, Walter Dnes <waltdnes@waltdnes.org> wrote:
> On Sun, Mar 22, 2015 at 09:25:53PM -0400, Fernando Rodriguez wrote
>
>> I guess gcc devs are careful when using the model numbers (Intel
>> lists 3 for Atoms, gcc uses only two so that may account for the
>> models I mentioned) but the chance of error is there. The -mno-xxx
>> flags would safeguard against it.
>
>   I have one of the earliest Atom chips.  Some people have a hard time
> believing this, but it's a 32-bit-only chip;  a couple of lines from
> /proc/cpuinfo
>
> model name      : Intel(R) Atom(TM) CPU Z520   @ 1.33GHz
> address sizes   : 32 bits physical, 32 bits virtual
>
>   Intel gives the CPU's specs at...
>
> http://ark.intel.com/products/35466/Intel-Atom-Processor-Z520-512K-Cache-1_33-GHz-533-MHz-FSB
>
> ...where it specifically says...
>
> Intel 64 # No
>
>   I want to make absolutely certain that "illegal instructions" are not
> compiled for it.

You will probably need to add -m32 to CFLAGS to avoid building 64-bit
objects on the 64-bit machine.