GNU libc 2.34 in unstable

The GNU libc version 2.34 has just been accepted into unstable. Getting it ready has been more challenging than other versions, as this version integrates a few libraries (libpthread, libdl, libutil, libanl) into libc. While this is handled transparently at runtime, there are a few corner cases at build time:

  • For backwards compatibility, empty static archives (e.g. libpthread.a) are provided, so that the linker options keep working. However a few cmake files shipped in some packages still reference the path to the shared library symlink (e.g. which is now removed.

  • A few symbols have also been moved from libresolv to libc and their __ prefix removed. While compatibily symbols are provided in the shared library for runtime compatiblity, this does not work at link time for static libraries referencing this symbol.

The next challenge is to get it migrating into testing!

For the adventurous persons, GNU libc 2.35 is now available in experimental. And as people keep asking, the goal is to get the just released GNU libc 2.36 into Bookworm.