Bug#896019: libglib2.0-0: undefined symbol g_date_copy breaking many programs

[Josef Kufner]

I hit this issue after yesterday upgrade from testing to the new stable 
too. There was an old file libglib-2.0.so.0.4200.1 from April 2014. Once 
I've removed it, mpd worked again.

I think that a simple consistency check about obsolete libraries might 
be helpful.

So far I've used this to detect old libraries not managed by dpkg:

find /lib/x86_64-linux-gnu -type f \
| grep -v -x -F -f \
    <(find '/var/lib/dpkg/info' -name '*.list' -print0 \
       | xargs -0 grep -h '^/lib/x86_64-linux-gnu' \
       | sort -u)