mapnik-config --cflags should provide these
mapnik-config --cflags should provide these

mapnik/Ruby-Mapnik,mapnik/Ruby-Mapnik,gravitystorm/Ruby-Mapnik,gravitystorm/Ruby-Mapnik,mapnik/Ruby-Mapnik,mapnik/Ruby-Mapnik,mapnik/Ruby-Mapnik,gravitystorm/Ruby-Mapnik,mapnik/Ruby-Mapnik,gravitystorm/Ruby-Mapnik,gravitystorm/Ruby-Mapnik,gravitystorm/Ruby-Mapnik