Hi,

I'd like to see all the .symbols files in libglvnd generating versioned
dependencies. That will be achieved by setting all the symbol versions
to something higher than 0.

This would mean:
* dependencies are no longer satisfiable by the virtual packages from
  src:mesa (<< 17) (a package built on buster won't be installable on
  stretch)
* it would simplify my work matching src:libglvnd package versions with
  src:nvidia-graphics-drivers packages, should I ever consider providing
  libglvnd package names again (since I could provide a version that is
  *less* than any src:libglvnd version, which doesn't work if the
  dependency other packages having on e.g. libgl1 is unversioned)


If you agree, I can prepare a patch.


Andreas