Found the issue. A seemingly innocent looking model of a Denon LP player downloaded as Collada file:

https://3dwarehouse.sketchup.com/model/146e084b-442e-41b3-a405-419684c216a3/Denon-SL-7D-Turntable

Works almost OK with SunFlow, crashes YafaRay instantly. When I change "edge_color*" invisible in materials, it works.

The resulting non-crashing render does have some texture or surface clipping issues (and I've noticed it on many other models from 3dWareHouse as well).