[NTLUG:Discuss] Re: AMD 64 Bit Distro -- your first 32/64-bit library issue

[Bryan J. Smith]

[ From:  LEAPLIST
  http://lists.leap-cf.org/pipermail/leaplist/2004-May/038663.html ]

David Simmonds wrote:  
> Guys,
> Asked a AMD64 Fedora programmer here in the North Texas LUG...I'm not
> sure his reply made it, so I'll post.

Justin M. Forbes wrote:  
> I might know a little bit about that, the ISOs for the x86_64 release
> were hand rolled by me since the red hat build system had specific
> issues with including mozilla32.  So here goes, mozilla in the Fedora
> project is using gtk2, which is included both i386 and x86_64.

Yeah, I noted that with "rpm -qR" and other library dependency checking
tools for both Mozilla and Firefox (from Fedora "Extras" aka Fedora.US)
on both RHL9 and FC1.  But I'm running on Athlon32 (2xAthlonMP2400+),
not Athlon64/Opteron.

I'm just checking into this for a colleague on our list.  He downloaded
the programs like Firefox from Mozilla, and GAIM from its project page,
and expected no issues.  I, among others, have encouraged him to use the
Apt/Yam capabilites for FC instead, to minimize issues.

Of course, I'm finding _no_ x86-64 Apt repositories out there.  Ugh. 
While he can still use some of the i386 repositories, it would be nice
to have the x86-64's as a preference so they are pulled from first, if a
program so exists for it.

> None of the x86_64 packages in Fedora Core include any 32bit
> libraries. 

Right.  I've seen that.  The i386 packages are sparce.

> They are simply x86_64 rebuilds of the same SRPM as the 32bit
> version.  All of the i386 packages included in the x86_64 release are
> the exact same rpms shipped in the i386 release of Fedora Core.

Right.

The issue is that even though x86-64's 64-bit memory mode is backward
compatible with i386 protected, you can't simply have 32-bit programs
using 64-bit libraries, etc..., without extensive re-work.  Hence why
Mozilla ships as a 32-bit program, so 32-bit plug-ins will work.

[ FYI:  My BS is in Electrical/Computer Engineering, with a focus on
architecture.  So I'm very familiar with the memory models of x86-64. ]

> Of note, in Fedora Core 2, mozilla is shipping 64bit, and when I
> update the FAQ for FC2, I will recommend the firefox rpms from
> fedora.us for those needing 32bit plugins (flash, java). It installs
> without any deps.

Thanx for that heads up!

> While installing i386 libs is generally fine, most will work, there are
> many lib packages which include a /usr/bin component, or an /etc config
> component which points to one path or another.

Right.  FC is using /usr/lib64 and other paths.  Symlinking to the non-
64-bit directories does not always solve the problem, because of the
memory mode differences.

> In this case, the RPMs will conflict, and installing them can have
> unpredictable results.

Exactomundo.

> As for extras, there will be a Fedora.us extras repository, with minor
> spec changes as we prepare for the official fedora extras roll out.
> This extras repository should appear at roughly the same time as FC2
> (May 17th), and will include packages built against FC2 only.  I am
> working on the rebuilds as time allows, but this week we are in crunch
> mode preparing for code freeze today. I also have it on good authority
> that the livna (freeworld, mp3, xine, etc) packages will be compiled
> x86_64 and available somewhere near the same timeframe. Fedora Core 2
> is shaping up to be a great platform for x86_64 as the 2.6 kernel is
> much more stable with the newer hardware.  

Very, very cool!  GCC 3.3+ and kernel 2.6+ seem to be the combo for x86_64.
Big thanks to SuSE for their early work with AMD to get this rolling, although
I assume Red Hat has come on strong as of late as well (even HP, who co-
designed IA-64, which is HP PA-RISC compatible, with Intel is now selling
competing Opteron systes ;-).

> Hope this helps, and do not hesitate to ping me on freenode as fedora64,
> or via email at 64bit_fedora at comcast.net if there is anything else I can
> help with.

Thanx.  I'm wondering if I can help any?  I might have a lot of free
time in the summer since I've left technology and am now a secondary
education teacher (only working on my masters in education starting
the end of this month).

-- Bryan "TheBS" Smith
   Big Headed, Very Little Knowledgeable
   Big Dreamer, Very Little Doer
   And Overall General Annoyance

P.S.  Oh yeah, as far as that "general annoyance" part, I might as well
start it on NTLUG.  The Sun Belt Conference is for panzies!  ;-ppp

-- 
Bryan J. Smith, E.I. -- Engineer, Technologist, School Teacher
b.j.smith at ieee.org