case $THIS_SUB_DEPENDS in
  DRI)
    if ! list_find "$MESA_GLX" dri;then
     list_add MESA_GLX dri
   fi
   ;;
  GLES2)
    if [[ "$MESA_GLES2" == "gles2=false" ]];then
      MESA_GLES="gles2=true"
    fi
    ;;
  *) echo "Unknown sub_depends $THIS_SUB_DEPENDS!"; return 1 ;;
esac
return 0