Linking against a specific library version: http://stackoverflow.com/a/3393372

old:

ld -lgif

new:

ld -l:libgif.so.1337
ld /lib/libgif.so.1337

This came up when writing https://github.com/azrdev/vlc-anigif. At the time, Archlinux had only giflib4 in its repos, but I needed functions from v5.