PostGIS has not been updated in some time and has fallen quite out of date at version 2.5.2 (2018 release) with the current version at 3.1. (2020 release). There are a couple of other dependencies that also need updating that will be linked to this ticket. This rev bump is also necessary as 2.5.2 has an error during building and rather than trying to fix the error on such an out of date package we should upgrade it.

Compatibility and Support Matrix for PostGIS:
https://trac.osgeo.org/postgis/wiki/UsersWikiPostgreSQLPostGIS

GIT Repository for PostGIS:
https://git.osgeo.org/gitea/postgis/

PostGIS:
Current - 3.1.2
Funtoo - 2.5.2

PostgreSQL: (autogenned in FL-11226)
Current - 13.3
Funtoo - 13.3

GEOS: (autogenned already)
Current - 3.9.1
Funtoo - 3.9.1

SFCGAL: (FL-8515)
Current - 1.3.10
Funtoo - (Needs to be added)

needs: needs CGAL (autogenned in FL-10496), openscenegraph (autogenned in FL-11214), and update to gmp (autogenned in FL-11216)

GDAL: (autogenned already)
Current - 3.3.0
Funtoo - 3.3.0

PROJ: (autogenned already)
Current - 8.0.1
Funtoo - 8.0.1

protobuf-c: (autogenned in FL-8516)
Current - 1.4.0
Funtoo - 1.3.1

json-c: (autogenned in FL-8517)
Current - 0.15
Funtoo - 0.13.1

The justification for this is an update of PostGIS so that we can use it, an update of a couple of packages to their more current versions, and the addition of SFCGAL will provide some needed functionality in PostGIS.
My field, GIS, is one that I am trying to learn other programs and move away from the ESRI stack. Having QGIS (recently updated) on Funtoo along with the ability to use PostGIS is important for me to expand my knowledge of other GIS prodcuts out there and it provides other GIS users with more options.

Edit: correction on json-c version numbers