2012.01.23 01:48 "Re: [Tiff] update on tiff 4.x in debian", by Jay Berkenbilt

On 01/22/2012 03:42 PM, Bob Friesenhahn wrote:

The configure script for CVS HEAD now supports a --enable-ld-version-script option to enable the test for versioned symbol capability and use it if it is available. This option is disabled by default until we decide exactly what we want to do.

Please let us know if the 3.9 branch of libtiff needs similar treatment in order to accomplish what Debian requires.

I just did a little investigation. I checked my old emails regarding libjpeg symbol versioning and I dumped symbols on a Linux system with libjpeg 6b and libjpeg 8 to see what was done.

Unfortunately, it will also be necessary to add symbol versioning to the 3.9 branch of libtiff and Debian would need to re-build and re-link all software depending on 3.[8-9].X (or which wants to remain so) with the 3.9.X version with the symbol versioning. All of the existing software linking against libtiff would need to be re-linked before libtiff 4.0 can be safely introduced.

Yes, I think this is accurate. However, in Debian, what we can do is have the release team do automatic binary NMUs for all existing packages, so getting everyone to relink with the versioned 3.9.x could be fully automated. Once that is done, then version 4.0.0 could be introduced, as you say. It will be a long process, but it will eventually complete.

Thanks so much for getting on this. I wish it had been on my radar prior to 4.0.0 too. Anyway, debian doesn't have 4.0.0 in unstable yet, and it doesn't matter whether we break compatibility with what's in experimental. I'd be really surprised if Fedora has it either. We're probably early enough in the life of 4.x to catch this before it becomes a big issue.

--Jay