GPL license versions between dependencies

Hi, While adding Freeradius to the Buildroot build system, we noticed that between the libtalloc library (GPL3) which Freeradius uses, and Freeradius (GPL2) there is a mismatch of GPL versions. What do others think? https://softwareengineering.stackexchange.com/questions/238748/can-gpl-v2-co... Regards, Matt Weber