Ununderstandable error in c++ (I think the matter is templates) [duplicate]

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• What is an undefined reference/unresolved external symbol error and how do I fix it? 27 answers

What does It mean?

/tmp/ccNLAlsX.o: In function `Level::LoadFromFile(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >)':
main.cpp:(.text+0xeb): undefined reference to `TiXmlDocument::TiXmlDocument(char const*)'
main.cpp:(.text+0xff): undefined reference to `TiXmlDocument::LoadFile(TiXmlEncoding)'
main.cpp:(.text+0x18c): undefined reference to `TiXmlElement::Attribute(char const*) const'
main.cpp:(.text+0x1b8): undefined reference to `TiXmlElement::Attribute(char const*) const'
main.cpp:(.text+0x1e5): undefined reference to `TiXmlElement::Attribute(char const*) const'
main.cpp:(.text+0x212): undefined reference to `TiXmlElement::Attribute(char const*) const'
main.cpp:(.text+0x25c): undefined reference to `TiXmlElement::Attribute(char const*) const'
/tmp/ccNLAlsX.o:main.cpp:(.text+0x2b8): more undefined references to `TiXmlElement::Attribute(char const*) const' follow
/tmp/ccNLAlsX.o: In function `Level::LoadFromFile(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >)':
main.cpp:(.text+0x2f8): undefined reference to `sf::Image::Image()'
main.cpp:(.text+0x311): undefined reference to `sf::Image::loadFromFile(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)'
main.cpp:(.text+0x36e): undefined reference to `sf::Color::Color(unsigned char, unsigned char, unsigned char, unsigned char)'
main.cpp:(.text+0x389): undefined reference to `sf::Image::createMaskFromColor(sf::Color const&, unsigned char)'
main.cpp:(.text+0x3be): undefined reference to `sf::Texture::loadFromImage(sf::Image const&, sf::Rect<int> const&)'
main.cpp:(.text+0x3d5): undefined reference to `sf::Texture::setSmooth(bool)'
main.cpp:(.text+0x3f1): undefined reference to `sf::Texture::getSize() const'
main.cpp:(.text+0x42b): undefined reference to `sf::Texture::getSize() const'
main.cpp:(.text+0x572): undefined reference to `TiXmlElement::Attribute(char const*) const'
main.cpp:(.text+0x591): undefined reference to `TiXmlElement::Attribute(char const*) const'
main.cpp:(.text+0x6d1): undefined reference to `TiXmlElement::Attribute(char const*) const'
main.cpp:(.text+0x71b): undefined reference to `sf::Sprite::Sprite()'
main.cpp:(.text+0x739): undefined reference to `sf::Sprite::setTexture(sf::Texture const&, bool)'
main.cpp:(.text+0x765): undefined reference to `sf::Sprite::setTextureRect(sf::Rect<int> const&)'
main.cpp:(.text+0x7c2): undefined reference to `sf::Transformable::setPosition(float, float)'
main.cpp:(.text+0x7ed): undefined reference to `sf::Color::Color(unsigned char, unsigned char, unsigned char, unsigned char)'
main.cpp:(.text+0x806): undefined reference to `sf::Sprite::setColor(sf::Color const&)'
main.cpp:(.text+0x9a0): undefined reference to `TiXmlElement::Attribute(char const*) const'
main.cpp:(.text+0x9bf): undefined reference to `TiXmlElement::Attribute(char const*) const'
main.cpp:(.text+0x9fa): undefined reference to `TiXmlElement::Attribute(char const*) const'
main.cpp:(.text+0xa19): undefined reference to `TiXmlElement::Attribute(char const*) const'
main.cpp:(.text+0xa42): undefined reference to `TiXmlElement::Attribute(char const*) const'
/tmp/ccNLAlsX.o:main.cpp:(.text+0xa6a): more undefined references to `TiXmlElement::Attribute(char const*) const' follow
/tmp/ccNLAlsX.o: In function `Level::LoadFromFile(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >)':
main.cpp:(.text+0xa8e): undefined reference to `sf::Sprite::Sprite()'
main.cpp:(.text+0xaac): undefined reference to `sf::Sprite::setTexture(sf::Texture const&, bool)'
main.cpp:(.text+0xadf): undefined reference to `sf::Sprite::setTextureRect(sf::Rect<int> const&)'
main.cpp:(.text+0xb10): undefined reference to `sf::Transformable::setPosition(float, float)'
main.cpp:(.text+0xb26): undefined reference to `TiXmlElement::Attribute(char const*) const'
main.cpp:(.text+0xb45): undefined reference to `TiXmlElement::Attribute(char const*) const'
main.cpp:(.text+0xb6d): undefined reference to `TiXmlElement::Attribute(char const*) const'
main.cpp:(.text+0xb9a): undefined reference to `TiXmlElement::Attribute(char const*) const'
main.cpp:(.text+0xbe7): undefined reference to `TiXmlElement::Attribute(char const*) const'
/tmp/ccNLAlsX.o:main.cpp:(.text+0xc34): more undefined references to `TiXmlElement::Attribute(char const*) const' follow
/tmp/ccNLAlsX.o: In function `Level::LoadFromFile(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >)':
main.cpp:(.text+0xc75): undefined reference to `sf::Sprite::setTextureRect(sf::Rect<int> const&)'
main.cpp:(.text+0xdd3): undefined reference to `TiXmlElement::Attribute(char const*) const'
main.cpp:(.text+0xe29): undefined reference to `TiXmlElement::Attribute(char const*) const'
main.cpp:(.text+0xfc5): undefined reference to `sf::Image::~Image()'
main.cpp:(.text+0x1122): undefined reference to `sf::Image::~Image()'
/tmp/ccNLAlsX.o: In function `Level::Draw(sf::RenderWindow&)':
main.cpp:(.text+0x13c9): undefined reference to `sf::RenderStates::Default'
main.cpp:(.text+0x13d0): undefined reference to `sf::RenderTarget::draw(sf::Drawable const&, sf::RenderStates const&)'
/tmp/ccNLAlsX.o: In function `main':
main.cpp:(.text+0x145e): undefined reference to `sf::String::String(char const*, std::locale const&)'
main.cpp:(.text+0x1479): undefined reference to `sf::VideoMode::VideoMode(unsigned int, unsigned int, unsigned int)'
main.cpp:(.text+0x14ad): undefined reference to `sf::RenderWindow::RenderWindow(sf::VideoMode, sf::String const&, unsigned int, sf::ContextSettings const&)'
main.cpp:(.text+0x16ae): undefined reference to `sf::Window::isOpen() const'
main.cpp:(.text+0x16cf): undefined reference to `sf::Window::pollEvent(sf::Event&)'
main.cpp:(.text+0x16ef): undefined reference to `sf::Window::close()'
main.cpp:(.text+0x170e): undefined reference to `sf::Color::Color(unsigned char, unsigned char, unsigned char, unsigned char)'
main.cpp:(.text+0x172a): undefined reference to `sf::RenderTarget::clear(sf::Color const&)'
main.cpp:(.text+0x174e): undefined reference to `sf::RenderStates::Default'
main.cpp:(.text+0x1767): undefined reference to `sf::RenderTarget::draw(sf::Drawable const&, sf::RenderStates const&)'
main.cpp:(.text+0x1779): undefined reference to `sf::Window::display()'
main.cpp:(.text+0x17b9): undefined reference to `sf::RenderWindow::~RenderWindow()'
main.cpp:(.text+0x17fa): undefined reference to `sf::RenderWindow::~RenderWindow()'
main.cpp:(.text+0x1945): undefined reference to `sf::RenderWindow::~RenderWindow()'
/tmp/ccNLAlsX.o: In function `TiXmlString::quit()':
main.cpp:(.text._ZN11TiXmlString4quitEv[_ZN11TiXmlString4quitEv]+0xc): undefined reference to `TiXmlString::nullrep_'
/tmp/ccNLAlsX.o: In function `TiXmlNode::NextSiblingElement(char const*)':
main.cpp:(.text._ZN9TiXmlNode18NextSiblingElementEPKc[_ZN9TiXmlNode18NextSiblingElementEPKc]+0x10): undefined reference to `TiXmlNode::NextSiblingElement(char const*) const'
/tmp/ccNLAlsX.o: In function `TiXmlNode::FirstChildElement(char const*)':
main.cpp:(.text._ZN9TiXmlNode17FirstChildElementEPKc[_ZN9TiXmlNode17FirstChildElementEPKc]+0x10): undefined reference to `TiXmlNode::FirstChildElement(char const*) const'
/tmp/ccNLAlsX.o: In function `TiXmlDocument::~TiXmlDocument()':
main.cpp:(.text._ZN13TiXmlDocumentD2Ev[_ZN13TiXmlDocumentD5Ev]+0x7): undefined reference to `vtable for TiXmlDocument'
main.cpp:(.text._ZN13TiXmlDocumentD2Ev[_ZN13TiXmlDocumentD5Ev]+0x2a): undefined reference to `TiXmlNode::~TiXmlNode()'
/tmp/ccNLAlsX.o: In function `Object::Object()':
main.cpp:(.text._ZN6ObjectC2Ev[_ZN6ObjectC5Ev]+0x57): undefined reference to `sf::Sprite::Sprite()'
/tmp/ccNLAlsX.o: In function `sf::Transformable::Transformable(sf::Transformable const&)':
main.cpp:(.text._ZN2sf13TransformableC2ERKS0_[_ZN2sf13TransformableC5ERKS0_]+0x4): undefined reference to `vtable for sf::Transformable'
/tmp/ccNLAlsX.o: In function `sf::Sprite::Sprite(sf::Sprite const&)':
main.cpp:(.text._ZN2sf6SpriteC2ERKS0_[_ZN2sf6SpriteC5ERKS0_]+0x34): undefined reference to `vtable for sf::Sprite'
main.cpp:(.text._ZN2sf6SpriteC2ERKS0_[_ZN2sf6SpriteC5ERKS0_]+0x3e): undefined reference to `vtable for sf::Sprite'
/tmp/ccNLAlsX.o: In function `Sprity::Sprity(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, float, float, float, float)':
main.cpp:(.text._ZN6SprityC2ENSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEES5_S5_ffff[_ZN6SprityC5ENSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEES5_S5_ffff]+0x35): undefined reference to `sf::Texture::Texture()'
main.cpp:(.text._ZN6SprityC2ENSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEES5_S5_ffff[_ZN6SprityC5ENSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEES5_S5_ffff]+0x47): undefined reference to `sf::Sprite::Sprite()'
main.cpp:(.text._ZN6SprityC2ENSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEES5_S5_ffff[_ZN6SprityC5ENSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEES5_S5_ffff]+0xc5): undefined reference to `sf::Texture::loadFromFile(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, sf::Rect<int> const&)'
main.cpp:(.text._ZN6SprityC2ENSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEES5_S5_ffff[_ZN6SprityC5ENSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEES5_S5_ffff]+0xe0): undefined reference to `sf::Sprite::setTexture(sf::Texture const&, bool)'
main.cpp:(.text._ZN6SprityC2ENSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEES5_S5_ffff[_ZN6SprityC5ENSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEES5_S5_ffff]+0x134): undefined reference to `sf::Sprite::setTextureRect(sf::Rect<int> const&)'
main.cpp:(.text._ZN6SprityC2ENSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEES5_S5_ffff[_ZN6SprityC5ENSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEES5_S5_ffff]+0x19d): undefined reference to `sf::Texture::~Texture()'
/tmp/ccNLAlsX.o: In function `Sprity::~Sprity()':
main.cpp:(.text._ZN6SprityD2Ev[_ZN6SprityD5Ev]+0x4c): undefined reference to `sf::Texture::~Texture()'
main.cpp:(.text._ZN6SprityD2Ev[_ZN6SprityD5Ev]+0x90): undefined reference to `sf::Texture::~Texture()'
/tmp/ccNLAlsX.o: In function `Level::Level()':
main.cpp:(.text._ZN5LevelC2Ev[_ZN5LevelC5Ev]+0x24): undefined reference to `sf::Texture::Texture()'
main.cpp:(.text._ZN5LevelC2Ev[_ZN5LevelC5Ev]+0x74): undefined reference to `sf::Texture::~Texture()'
/tmp/ccNLAlsX.o: In function `Level::~Level()':
main.cpp:(.text._ZN5LevelD2Ev[_ZN5LevelD5Ev]+0x36): undefined reference to `sf::Texture::~Texture()'
main.cpp:(.text._ZN5LevelD2Ev[_ZN5LevelD5Ev]+0x62): undefined reference to `sf::Texture::~Texture()'
/tmp/ccNLAlsX.o: In function `sf::Sprite::~Sprite()':
main.cpp:(.text._ZN2sf6SpriteD2Ev[_ZN2sf6SpriteD5Ev]+0x8): undefined reference to `vtable for sf::Sprite'
main.cpp:(.text._ZN2sf6SpriteD2Ev[_ZN2sf6SpriteD5Ev]+0x12): undefined reference to `vtable for sf::Sprite'
main.cpp:(.text._ZN2sf6SpriteD2Ev[_ZN2sf6SpriteD5Ev]+0x27): undefined reference to `sf::Transformable::~Transformable()'
collect2: error: ld returned 1 exit status