Bug#83669: Shared libraries

[Ian Jackson <ian@davenant.greenend.org.uk>]

Ben Collins writes ("Bug#83669: Shared libraries"):
> On Fri, Jan 26, 2001 at 07:34:08PM +0000, Ian Jackson wrote:
> > 
> >  foo-dev (2.1)  /usr/include/foo.h
> >                 /usr/lib/libfoo.so              (copy of actual library)
> > 
> 
> Can we say archive, system, mirror and update bloat horror!? DO you
> realize what this would mean for lib packages like xlibs and libc6?

Could you please be more specific ?

>   I think your setup is completely broken, since it will be linking
> against one version of the library, yet running against another
> (remember the runtime in your scenario will now be different than
> the link time one).

But we *already* support linking against one version and running with
another.  That's the whole point of shared libraries.  In particular,
it will make it possible (not essential, but possible) to build
binaries against an older version of the library than you currently
have installed; this will produce binaries which will work both with
that older library on other systems, and of course (given that ABI's
are supposedly upward-compatible) with the one you have installed.

Have you never had the experience of a system running stable which
needs just one package from unstable ?  You have to install the libc
from unstable, so you have to install the libc-dev from unstable, so
you have to install the libfoobar-dev from unstable for nearly every
foobar, so you have to install the libfoobar from unstable for nearly
every libfoobar, and suddenly the system isn't running stable any
more.

> This is bad, and creates plenty of problems due to the inconsistencies
> you create. If we encourage maintainers to link against libraries for
> which they cannot test the runtime, then you are asking for plenty of
> untested packages ending up in the distribution.

I'm not saying that maintainers should routinely usually have
different -dev and runtime packages installed.  On the contrary, a
testing system should have the latest versions, which will correspond.

I don't understand what you mean by `link against libraries for which
they cannot test the runtime'.

Ian.