On 09/21/2015 09:16 AM, Simon McVittie wrote:
> Source: ppl
> Version: 1:1.1-6
> Severity: serious
> Justification: ABI break since stable
> Tags: sid stretch
> User: debian-...@lists.debian.org
> Usertags: libstdc++-cxx11
>
> Background[1]: libstdc++6 introduces a new ABI to conform to the
> C++11 standard, but keeps the old ABI to not break existing binaries.
> Packages which are built with g++-5 from experimental (not the one
> from testing/unstable) are using the new ABI. Libraries built from
> this source package export some of the new __cxx11 or B5cxx11 symbols,
> dropping other symbols. If these symbols are part of the API of
> the library, then this rebuild with g++-5 will trigger a transition
> for the library.
>
> In the case of ppl, at least float_mpq_to_string() appears to change
> its ABI in this way, so a transition does appear to be needed.
> The transition normally consists of renaming the affected library
> packages, adding a v5 suffix (libppl13v5). The SONAME should not be
> changed when doing this.
>
> If an upgrade to a new upstream SONAME is already planned, and that
> SONAME has never been available in Debian compiled with g++-4, then an
> alternative way to carry out the transition would be to bump the
> SONAME. However, the libstdc++ transition has been going on for a
> month already, and anything that makes it take longer is bad for Debian,
> so introducing new upstream code is not desired at this stage.
>
> These follow-up transitions for libstdc++ are not going through exactly
> the normal transition procedure, because many entangled transitions are
> going on at the same time, and the usual ordered transition procedure
> does not scale that far. When all the C++ libraries on which this library
> depends have started their transitions in unstable if required, this
> library should do the same, closing this bug; the release team will deal
> with binNMUs as needed.
>
> Looking at the build-dependencies of ppl, there doesn't seem to be any
> C++, so this transition seems to be ready to go.
>
> The package might be NMU'd if there is no maintainer response. The
> release team have declared a 2 day NMU delay[2] for packages involved
> in the libstdc++ transition, in order to get unstable back to a usable
> state in a finite time.
>
> Regards,
> S
>
> [1] https://wiki.debian.org/GCC5#libstdc.2B-.2B-_ABI_transition
> [2] https://lists.debian.org/debian-devel-announce/2015/08/msg00000.html
Dear Simon,
I am unfamiliar with many of the terms you use in your message.
For the little I understand, I am in favor of the resolutions
you propose, but I don't know how to implement them (I mean,
without changing upstream code). If you can send more detailed
instructions, we will be glad to try and implement them.
Kind regards,
Roberto
--
Prof. Roberto Bagnara
Applied Formal Methods Laboratory - University of Parma, Italy
mailto:bagn...@cs.unipr.it
BUGSENG srl - http://bugseng.com
mailto:roberto.bagn...@bugseng.com
