libguestfs, guestfs-tools and virt-v2v currently depend on Jansson (a JSON library). libvirt recently moved to using json-c instead. For consistency with libvirt, to avoid potentially conflicting symbols, and to reduce package maintenance, we should make the same change in libguestfs, guestfs-tools and virt-v2v.

There should be no user-visible change at all.

The same change was made to Fedora Rawhide recently.

(Note that libguestfs-appliance will still requires jansson, because some tools that we use inside the appliance are using it.)