Bug#951030: Bug#950859: cegui-mk2: FTBFS with boost171 and new cmake and symbol changes

[Olek Wojnar]

Hi Dimitri,

On Sat, Feb 8, 2020 at 7:37 PM Dimitri John Ledkov <xnox at ubuntu.com> wrote:

> Yes there is a way.
>
> You can provide libcegui-mk2-x.y.z-boost171
> And then rewrite shlib deps to require a dep on
> libcegui-mk2-x.y.z-boost171 ( >= X.y.z)
>
> That way things that build against this new lib get the right dep, and
> whenever cegui is NMUed for new boost Abi autochanges.
>
> However, when you switch to this scheme either the library package needs
> to change name, or you need to declare breaks on your reverse deps, to
> prevent partial upgrade
>
> Boost does similar to encode python versions and icu. And many other deb
> languages do similar things like ocaml, gch, etc.
>

Thanks for the recommendation! Unfortunately, that's a bit more than I can
do in the near future so I've split this off from the rest of your bug
report so that I can hopefully work on it at some point in the future.
Patches welcome of course if this is something you're more familiar with
and have the time! ;)

-Olek


>
> On Sat, 8 Feb 2020, 17:48 Olek Wojnar, <olek at debian.org> wrote:
>
>> Hi Dimitri,
>>
>> Thanks for the bug report, and thanks for the patch!
>>
>> On 2/7/20 8:49 AM, Dimitri John Ledkov wrote:
>> > Package: cegui-mk2
>> > Version: 0.8.7-5
>> > Severity: serious
>> > Tags: patch
>> > Justification: ftbfs
>> >
>> > Dear Maintainer,
>> >
>> > cegui-mk2 ftbfs with new cmake & boost1.71 due to change in cmake
>> > policy w.r.t. boost version detection (it is now more normal). See
>> patch attached.
>>
>> Thank goodness for them making it more normal! I was not a fan of that
>> old system.
>>
>> > I am currently in process of migrating to boost1.71 in Ubuntu, which
>> > has not started yet in Debian but is upcoming.
>> >
>> > When built against boost1.71 symbols are dropped and changed. It seems
>> > as if cegui-mk2 re-exports boost symbols, and thus boost abi change in
>> > templates leakes in the change of cegui-mk2 libraries ABI change.
>> >
>> > How should this be handled?
>> >
>> > Is there a new upstream release of cegui that we can package in
>> > experimental, always built against boost1.71 with new symbols?
>>
>> No, upstream has not done a new release in a while. Although I can (and
>> plan to) package the current version in experimental once boost1.71
>> lands there. Since I don't follow Boost, a notification in this bug
>> report would be appreciated.
>>
>> > Or shall i just blindly update the symbols file, rebuild ember and
>> > hope for the best?
>> >
>> > How was this handled in cegui-mk2 before, when boost changed without
>> > cegui-mk2 new upstream releases?
>>
>> I've only recently taken a more-active role in maintaining this package.
>> I think I previously only submitted a few NMUs. But, I believe that what
>> you listed is exactly what happened. I know I saw that with Ember (which
>> I *have* been maintaining for a while).
>>
>> If you have any suggestions for a better, less-reactive, way forward on
>> this I'm certainly open to it!
>>
>> > I would like to avoid diverging ABI between ubuntu & debian here.
>>
>> Absolutely! I'm a big fan of keeping Debian and Ubuntu closely
>> synchronized.
>>
>> -Olek
>>
>>
>>