[LLVMdev] Call for Help: Testing

[David Greene]

On Tuesday 06 April 2010 14:12:04 Duncan Sands wrote:
> Hi David,
>
> > The second problem is the lack of x86-32 testing on Linux.  This is only
> > going to get worse as x86-32 desktops and servers continue to disappear.
>
> this is not really a problem if you have root access on an x86-64 box.  It
> is quite easy to install a 32 bit chroot environment.  That's what I'm
> using on my laptop for testing x86-32.  You really can't tell it's not the
> real thing. The problem I have is that I don't have root access to the
> machines I'm using for running testers, and the administrator doesn't want
> to set up such a 32 bit environment.

Yes, this is doable, but it's complicated.  To get adequate testing we need
to make it as simple as possible for new users to participate.  Either we
need a step-by-step recipe or we need a simpler approach.  Either this or
virtualization would work but both are complicated to set up, raising the
bar to participate.

A chroot doesn't run a 32-bit kernel so virtualization would emulate the
32-bit environment slightly better.  But I don't know if that's all that
significant in the end.

> > Another alternative is to add a buildbot recipe that builds x86-32
> > targets on x86-64 machines.  Is this already available?  If so, it seems
> > we should already be running sufficient x86-32 testing.  As we apparently
> > don't have enough such testing, I assume we don't have this kind of
> > recipe available yet. I think most Linux x86 distributions ship multilib
> > compilers so this should be possible without too much trouble.
>
> I am working on such a recipe for testing 32 bit dragonegg, but so far it
> fails mysteriously and I didn't figure it out yet.

Great!

It strikes me that we also have an issue with gcc version.  As demonstrated
by PR6616, compiler versions matter.  It seems we will need to settle on a
standard compiler for each release to avoid some of the confusion that can
delay releases.  What do the buildbots use?  Unfortunately, this again makes
things more complicated as it requires testers to install specific versions of
compilers.  Linux distributions don't always make that easy.

But one step at a time.  Getting more 32-bit Linux testing is the first step.

                           -Dave