Patch: RFC: bump libtool version

[Matthias Klose]

Andrew Haley schrieb:
> Matthias Klose writes:
>  > Tom Tromey schrieb:
>  > > Matthias pointed out on irc that we ought to bump the libgcj version
>  > > on trunk.  I think we also need this on the RH 4.1 merge branch.
>  > > 
>  > > I thought I would see if there are any comments before I check this in.
>  > 
>  > one more thing; currently we do not change the versioned gcj subdir when
>  > we change the libgcj soversion. At least for distributions like debian
>  > and ubuntu that means that we do have file conflicts if we bump the
>  > libgcj soversion and keep the gcc version (having packages like libgcj7
>  > and libgcj8).
> 
> Why?  What exactly causes the problem?

The ABI/API version of a shared library is encoded in the package name;
this is standard technique used in these distributions. when the
soversion is changed, the package with the old soversion can be kept
installed together with packages depending on that version. Until all
packages depending on the old library package are rebuilt you can have
both library packages installed together (if files in those library
packages don't conflict). If you currently backport a new libgcj to a
released gcc version, you do have the file conflicts in
/usr/lib/gcj-<gcc-version>, although the library ABI changed, not
anything of the gcc/gcj ABI. You could avoid these problems installing
into /usr/lib/libgcj<libgcjsoversion>. You don't have this problem if
you do not support partial upgrades or rebuild your distribution from
scratch.

  Matthias