problem with __init_cpu_features()

[Carlos O'Donell]

On Wed, May 18, 2016 at 10:55 AM, Carlos O'Donell
<carlos@systemhalted.org> wrote:
> On Wed, May 18, 2016 at 10:37 AM, The Source <thesourcehim@gmail.com> wrote:
>> Hello, I'm trying to run my application on Cyrix Cx486SLC based system. But
>> application (built for i486 as well as glibc) crashes on illegal instruction
>> inside __init_cpu_features(). As far as I understand this CPU does not
>> support cpuid (/proc/cpuinfo reports cpuid level -1 and /dev/cpu/0/cpuid can
>> not be read with i/o error), so that might be the problem. Is there a way to
>> avoid using __cpuid()? My glibc version is 2.22
>
> You must use specific CFLAGS or CC to indicate you are building for a
> pre-i586 target, that will disable unconditional cpuid usage, and
> enable the checks required to verify cpuid is usable.
>
> If you are cross-compiling from an x86_64 box I would recommend
> CC="gcc -m32 -march=i486" instead to ensure that regardless of flags
> you build for i486.
>
> Just to check I kicked off a build for i486 locally to see if runs
> into any problems.

i486 builds just fine and I verified it calls __get_cpuid_max to check
for cpuid feature.

Test results look good too.

Cheers,
Carlos.