Source: gdcm Version: 2.4.4-4 Severity: serious Justification: breaks ABI without a package rename Control: block -1 by 797673 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 gdcm, std::string appears in symbols that are explicitly imported, so it seems very likely that a transition is needed. The transition consists of renaming the affected library packages, adding a v5 suffix (libgdcm2.4v5, etc.). The SONAME should not be changed. 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. In the case of gdcm: * poppler and vtk have started their transitions * socket++ does not appear to need a transition * the other library dependencies appear to be C APIs so I think this is ready to go. The package is likely to 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