Procedure to build GIMP 2.10.0 on Mageia 6
To build GIMP 2.10.0
on Mageia 6, the following packages needs to be upgraded as well.

It is important that you do this in this order, but beware that you will, kind of, break your installation of Mageia somewhat.
Procedure to build GIMP 2.10.0 on Mageia 6
- Freetype2 - version 2.9
- Fontconfig - version 2.3.5
- babl - version 0.1.46
- gegl - version 0.4.0
- libmypaint - 1.3.0 with a patch for gegl-0.4