In fact I had FREECAD_USE_EXTERNAL_KDL=ON. If I set it to OFF everything works, but with the following corrections, which I do not know whether are essential or not diff --git a/src/Mod/Robot/App/kdl_cp/trajectory_stationary.hpp b/src/Mod/Robot/App/kdl_cp/trajectory_stationary.hpp index 824dbef..f36...