On 14/07/14 22:36, Aurelien Jarno wrote: > Hi all, > > glibc 2.19 has changed the libc ABI on s390, more specifically the > setjmp/longjmp functions [1] [2]. Symbol versioning is used to handle > some cases, but it doesn't work when a jmp_buf variable is embedded > into a structure, as it changes the size of the structure. The result > is that mixing programs or libraries built with 2.18 with ones built > with 2.19 do not work anymore, usually they end up with a segmentation > fault. Some persons from this list have experienced that with perl. > > We first thought it was limited to a few packages (even if all perl is > already more than that), but as time goes more and more issues are > found. libpng and gauche are also affected, the issue with mono is > also likely due to this ABI change. > > According to upstream [3], the problem is that Debian doesn't do a mass > rebuild, which is the strategy chosen by Red Hat to handle^Wworkaround > this issue. This means some programs might segfault during the upgrade, > or on partially upgraded systems. > > Now we have to chose a strategy for Debian. I see multiple options: > > 1) Ignore the issue and just rebuild (binNMU) the packages that seems > affected when we discover them. This means partial upgrades will likely > be broken, and that we might discover some broken packages only after > the jessie release. > > 2) Rebuild (binNMU) all packages. This means partial upgrades will > likely be broken. > > 3) Bump the soname of affected packages and rebuild their reverse > dependencies. It is the solution that is currently being implemented for > perl. It clearly won't scale if more broken packages (and even for > libpng) are discovered as it requires a source upload and a transition > handled by the release team. It also means breaking the ABI compatibility > with other distributions. > > 4) Bump the libc soname to libc.so.6.1 and do a libc transition. This is > probably what upstream should have done instead of breaking the ABI. > This is a huge work though, and this also means breaking the ABI > compatibility with other distributions. > > 5) Revert the ABI change. This is likely just postponing the problem as > the change is required to support future hardware. This also means > breaking the ABI compatibility with other distributions. > > 6) simply drop the s390x port and tell users to either use an other > distribution or use Debian on other hardware.
Status update: So in the end upstream has agreed to revert the change that broke the ABI, and that's what we will do as well. The biggest thing we need to revert with it is the perl ABI, but since we're going to update to perl 5.20 in a couple of weeks, we'll do the two at the same time to avoid having two perl transitions (one everywhere and another one on s390x). Emilio -- To UNSUBSCRIBE, email to debian-glibc-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: https://lists.debian.org/53d6b4cb.4080...@debian.org
