.gitignore and .gitattributes files present:
/qtlocation/src/3rdparty/mapbox-gl-native/.gitignore
/qtlocation/src/3rdparty/mapbox-gl-native/src/3rd_party/geometry.hpp/.gitignore
/qtlocation/src/3rdparty/mapbox-gl-native/src/3rd_party/mapbox-gl-shaders/.gitignore
/qtlocation/src/3rdparty/mapbox-gl-native/src/3rd_party/earcut/.gitignore
/qtlocation/src/3rdparty/mapbox-gl-native/src/3rd_party/rapidjson/.gitignore
/qtlocation/src/3rdparty/mapbox-gl-native/src/3rd_party/protozero/.gitignore
/qtlocation/src/3rdparty/mapbox-gl-native/src/3rd_party/protozero/doc/.gitignore
/qtlocation/src/3rdparty/mapbox-gl-native/src/3rd_party/protozero/test/.gitignore
/qtlocation/src/3rdparty/mapbox-gl-native/src/3rd_party/protozero/test/t/.gitignore
/qtlocation/src/3rdparty/mapbox-gl-native/src/3rd_party/kdbush.hpp/.gitignore
/qtlocation/src/3rdparty/mapbox-gl-native/src/3rd_party/polylabel/.gitignore
/qtlocation/src/3rdparty/mapbox-gl-native/src/3rd_party/geojson-vt-cpp/.gitignore
/qtlocation/src/3rdparty/mapbox-gl-native/src/3rd_party/geojson-vt-cpp/deps/gyp/.gitignore
/qtlocation/src/3rdparty/mapbox-gl-native/src/3rd_party/geojson-cpp/.gitignore
/qtlocation/src/3rdparty/mapbox-gl-native/src/3rd_party/supercluster.hpp/.gitignore
/qtlocation/src/3rdparty/mapbox-gl-native/src/3rd_party/variant/.gitignore
/qtlocation/src/3rdparty/mapbox-gl-native/platform/ios/uitest/.gitignore
/qtlocation/src/3rdparty/mapbox-gl-native/platform/android/.gitignore
/qtlocation/src/3rdparty/mapbox-gl-native/.mason/.gitignore
/qtlocation/src/3rdparty/mapbox-gl-native/src/3rd_party/rapidjson/.gitattributes
/qtlocation/src/3rdparty/mapbox-gl-native/src/3rd_party/protozero/.gitattributes

/qtlocation/src/3rdparty/mapbox-gl-native is new feature that was not present in Qt5.8.