Version 4.12.4 is available upstream. Please consider updating!
It seems that version 4.12.4 is available upstream, while the latest version in the Gentoo tree is 3.24.38. You think this warning is false? Read more about it here.
gtk-update-icon-cache is a tool from GTK+ to update icons and themes
It is split from the GTK+ sources by the Gentoo Gnome team to help
GTK+ 2 and 3 to co-exist better by extracting the single conflicting