from /home/pi/supertux/src/addon/addon_manager.hpp:28, from /home/pi/supertux/src/addon/addon_manager.cpp:20: /usr/include/glm/gtx/type_trait.hpp:16:3: error: #error "GLM: GLM_GTX_type_trait is an experimental extension and may change in the future. Use #define GLM_ENABLE_EXPERIMENTAL before including it, if you really want to use it." # error "GLM: GLM_GTX_type_trait is an experimental extension and may change in the future.