[CentOS-devel] CentOS-4.9 SRPMS

Sat Feb 19 17:46:03 UTC 2011
Lamar Owen <lowen at pari.edu>

On Saturday, February 19, 2011 12:02:07 pm js wrote:
> I'm curious how you can patch the build system.

There have been pointers to the buildsys RPM's on dev.centos.org before (and there have been some odd statements around them, but you'll need to look through the archives of the mailing lists to really get those (and I'm not sure I understand all of what's said about that....)).  

You'll find it educational to look and see what is and is not in those RPM's.  I'm not going to give you a step-by-step for that, not because it's secret sauce, but, as in making good smooth bacon gravy, you have to try it yourself, and then you'll understand.  (yes, I can make gravy, and while there aren't really any secret ingredients in gravy (the list: bacon grease, enough self-rising flour to absorb almost all of the grease, milk, and a pinch of salt and pepper) it's all in the way it's mixed, and you have to learn that by feel.)  The rpm command gives you all the tools you need to look at what is, and is not, found in the buildsys RPM's hosted on dev.centos.org (see   http://dev.centos.org/centos/buildsys/5/buildsys-build-0.5-6.el5.centos.7.noarch.rpm )

But do note Karanbir's note at http://lists.centos.org/pipermail/centos-devel/2010-May/005545.html

I'm still digesting what that means, but, given the age of the buildsys-build RPM's on dev.centos.org (IE: they're old!) makes me wonder.  And, well, if Karanbir and whomever else want to keep secret sauces or techniques, that's their choice, honestly.

Patching the buildsystem starts with patching that RPM, assuming that RPM has anything to do with the current build process.....  While that is far from the only piece of the build system, it is the key piece, since it describes what the minimum buildroot for mock looks like.

Then what wolfy wrote on this thread as well; digest that, and play with it.

> I don't remember (I think it was for Centos4 I think), but Centos fix a 
> bug that was present in RHEL4;
> So ... sometimes you have no choice; you need to add a patch and hope it 
> will no have consequences.

Well, that's why I say it's a goal to have no patches; if you have to patch you have to patch, just means you missed your goal on that package.

> That make sense,
> So Centos, because of that, need to be like it is today... because this 
> is only a "perfect clone of RHEL" :-/

Yep.

> but it will be very useful to be able to reproduce the build env anyway; 
> seems to be a recurrent request.

Going forward, reproducing the upstream builds (really, that's what we're after anyway, not a rebuild of a rebuild) will involve koji, as that's the tool built for the task.  It is not a small tool.

But, as a fnal note (typo/pun intended), please read what Troy has to say in
http://listserv.fnal.gov/scripts/wa.exe?A2=ind1011&L=SCIENTIFIC-LINUX-DEVEL&P=R531&I=-3