Scheduled Maintenance: We are aware of an issue with Google, AOL, and Yahoo services as email providers which are blocking new registrations. We are trying to fix the issue and we have several internal and external support tickets in process to resolve the issue. Please see: viewtopic.php?t=158230

 

 

 

How dangerous is it to pull libc from unstable?

Linux Kernel, Network, and Services configuration.
Post Reply
Message
Author
Particle
Posts: 19
Joined: 2018-02-03 18:59

How dangerous is it to pull libc from unstable?

#1 Post by Particle »

In the pursuit of obtaining the most up-to-date Mesa libs, I've been pulling Mesa in from Experimental using apt pinning. Everything else on the system is Testing. The latest version of Mesa in Experimental requires a newer libc6 build, and I find that it's available from Unstable.

How dangerous would it likely be, generally speaking, to update libc (ie libc-bin, libc6, locales) in this fashion?

While I don't imagine there is a lot happening in the world of C standard libraries, it is nonetheless a fundamental cornerstone for a large part of the system. As such it is scary to contemplate coloring outside the lines a little bit.

Admittedly, I'm not a fan of Mr. Frankendebian but as a game player it's nearly unavoidable. I would prefer to stay in-house so to speak for repos instead of relying on popular private repos for graphics software that aren't even targeting Debian at all.

Bulkley
Posts: 6383
Joined: 2006-02-11 18:35
Has thanked: 2 times
Been thanked: 39 times

Re: How dangerous is it to pull libc from unstable?

#2 Post by Bulkley »

Installing one package from another repository might work; the pain is often in dependencies dragged in with it. I suggest you try it but before you do . . . . make a complete backup, preferably a clone! Have you considered using a virtual machine to experiment with? A live USB?

Get a notebook and document everything.

Segfault
Posts: 993
Joined: 2005-09-24 12:24
Has thanked: 5 times
Been thanked: 17 times

Re: How dangerous is it to pull libc from unstable?

#3 Post by Segfault »

Since glibc is probably the most important library in your Linux system great care is taken to make it backwards compatible. So I'd say glibc upgrade is 99.99% safe.

Particle
Posts: 19
Joined: 2018-02-03 18:59

Re: How dangerous is it to pull libc from unstable?

#4 Post by Particle »

Do you mean something different than using Debian backports? Those are packages from Testing I believe, but only Experimental has the latest Debian builds of Mesa.

Particle
Posts: 19
Joined: 2018-02-03 18:59

Re: How dangerous is it to pull libc from unstable?

#5 Post by Particle »

Very interesting. I've built the personal backports as the guide indicates, but I am left with one question. Can this be made to cross-compile? My system is 64-bit, but I'll need to build 32-bit x86 libs as well.

User avatar
Head_on_a_Stick
Posts: 14114
Joined: 2014-06-01 17:46
Location: London, England
Has thanked: 81 times
Been thanked: 132 times

Re: How dangerous is it to pull libc from unstable?

#6 Post by Head_on_a_Stick »

Particle wrote:My system is 64-bit, but I'll need to build 32-bit x86 libs as well.
https://packages.debian.org/stretch/pbuilder
deadbang

Particle
Posts: 19
Joined: 2018-02-03 18:59

Re: How dangerous is it to pull libc from unstable?

#7 Post by Particle »

Is there a way to do it using dpkg-buildpackage instead? pbuilder is throwing errors when I try it.

User avatar
Head_on_a_Stick
Posts: 14114
Joined: 2014-06-01 17:46
Location: London, England
Has thanked: 81 times
Been thanked: 132 times

Re: How dangerous is it to pull libc from unstable?

#8 Post by Head_on_a_Stick »

Particle wrote:pbuilder is throwing errors when I try it
If you share the errors here then we might be able to help you.

Pro tip: always tell us the *exact* commands that you used and also provide the configuration files, if any.
deadbang

User avatar
stevepusser
Posts: 12930
Joined: 2009-10-06 05:53
Has thanked: 41 times
Been thanked: 71 times

Re: How dangerous is it to pull libc from unstable?

#9 Post by stevepusser »

Well, I backported Mesa 18.1.9 on Stretch in pbuilder for both amd64 and i386 for the MX repos, so I wouldn't think it's one of those packages that won't build in pbuilder, like Pale Moon or Firefox.

Can you post those errors? Believe me, I've made a zillion wrong steps, so probably have seen more errors in pbuilder than you would believe.
MX Linux packager and developer

Particle
Posts: 19
Joined: 2018-02-03 18:59

Re: How dangerous is it to pull libc from unstable?

#10 Post by Particle »

I did eventually get pbuilder to run after thumbing through the man pages and Google for a while, but I do have some questions that hopefully you can help me with.

I tried to cross-compile by setting up the chroot with this command:
sudo pbuilder create --distribution testing --architecture i386

Then I made an empty folder and issued this command inside:
dget -x http://deb.debian.org/debian/pool/main/ ... ~rc5-1.dsc

And finally, I built the packages using:
sudo pbuilder build *.dsc

Questions about pbuilder:
1) Is this the right way to cross-compile for my purposes?
2) Is there a single, shared chroot stored somewhere or is it specific to my terminal?
3) How should I clean up the environment/chroot when I'm done?
4) Can I enter the chroot pbuilder makes in order to customize it a bit? *
5) Can I set the revision string to something like ~bpo# so that if I recompile it the build version will be seen?
6) If I wanted to build for both amd64 and i386, do I have to clear the chroot and start over each time I switch back and forth?

* I would like to install llvm-7 and make a symlink for llvm-config-7 -> llvm-config so that the package will be built with that instead of llvm-6 which testing defaults to. I believe this to be required for some games to work.

User avatar
stevepusser
Posts: 12930
Joined: 2009-10-06 05:53
Has thanked: 41 times
Been thanked: 71 times

Re: How dangerous is it to pull libc from unstable?

#11 Post by stevepusser »

I use the pdebuild command myself, for i386 on Stretch:

Code: Select all

OS=debian DIST=stretch ARCH=i386 pdebuild  --debbuildopts "-B -jauto" 
The "-B" makes sure the arch-independent packages don't get built, since I already have those from my first amd64 build. "-jauto" uses all available cores if the package supports parallel builds. Those OS, DIST, and ARCH variables probably aren't needed, but I'm using a custom .pbuilderrc based on https://jodal.no/2015/03/08/building-ar ... -pbuilder/

You can also make changes to the version just like it says how to in the "Simple Backports" how to. Once you have your build done on your local install, delete the source folder and then re-extract those with

Code: Select all

dpkg-source -x name-of.dsc-file
Then go into the new source folder and run the command for pbuild or pdebuild to cross-compile the same version.

I think pbuild sets up a new chroot for each build, and cleans up afterwards automatically. The base .tgz tarball for each distrelease, along with the /build folder where the builds actually take place, are in /var/cache/pbuild. The /build folder should be empty after a sucessful build.

You should be able to edit the debian/control and rules files to use llvm-7 instead of 6 without messing with an llvm-config file.
MX Linux packager and developer

User avatar
stevepusser
Posts: 12930
Joined: 2009-10-06 05:53
Has thanked: 41 times
Been thanked: 71 times

Re: How dangerous is it to pull libc from unstable?

#12 Post by stevepusser »

Hmmm---I'm trying to backport Mesa 18.2.6 from Sid to Stretch, and it already requires llvm-7, so I have that heavy long build running.
MX Linux packager and developer

Post Reply