On 22.09.2015 13:52, Bálint Réczey wrote:
Hi, 2015-08-30 15:46 GMT+02:00 Andreas Metzler <ametzler@bebt.de>:In gmane.linux.debian.backports.general Daniel Pocock <daniel@pocock.pro> wrote: [...]As part of the GCC5 update[1], one of the binary packages built from openrpt has been renamed from libopenrpt1 to libopenrpt1v5 - see bug #791230[2] - and that is the version that will be in testing.If I understand the rules for backports correctly, backports is supposed to contain the same thing that is in testing.Given that unstable and testing will use GCC5 and jessie-backports should be using the GCC 4.9 from jessie, what is supposed to happen? Will GCC5 be available to compile for backports and should such packages declare a dependency on the newer libstdc++? Or is it permitted to make uploads to jessie-backports without the "v5" suffix, so the package name in backports won't be the same as the package name in testing? Or something else?[..] Hello, afaict the only way to handle this is to undo any -v5 renaming for backports. Backporting gcc5 and using it to compile selective backports is not an option since one cannot mix (all) c++ code built with gcc49 and with gcc5. (Except for those libraries that do not need a gcc5 transition)....Later on it might even become necessary to actually make a reverse gcc transition (v4) for backports of C++ libraries which had a soname bump in sid after gcc5 and therefore do not carry a v5 name. That is all just afaict, and needs confirmation by backports admin with better C++ foo than me.It seems reasonable to me. It think we would also need to add Breaks/Replaces to the unstable/testing versions: jessie-bpo: libfooNv4 testing: libfooN (Breaks: libfooNv4; Replaces: libfooNv4) I plan back-porting some affected packages but it would be nice if Matthias and backports admins could agree on the best practice first and add this to the transition documentation: https://wiki.debian.org/GCC5
you should differentiate two cases: - if just the library package was renamed, you should undo the v5 changes. - if you had a soname bump, you have to both change the jessie-bpo package, and add the breaks/replaces for unstable/testing. using the v4 suffix there seems to be sensible.Feel free to add a new section to the wiki page. Note that at least the gcc-5 packaging uses the gcc4-compatible ABI when built for jessie. So even if you decide to backport this one, the above changes are necessary.
Matthias