https://bugs.freedesktop.org/show_bug.cgi?id=96634
--- Comment #2 from Emil Velikov emil.l.velikov@gmail.com --- Note that closed source drivers overwrite multiple files - libGL.so and libglx.so as a bare minimum.
In the log that you've attached - the AMD Proprietary libglx.so is used, which won't work with the open source xf86-video-amdgpu or libGL (coming from mesa).