c++ - 在架构 x86_64 clang : error: linker command failed with exit code 1 (use -v to see invocation) 中找不到符号

Question

我收到此消息“在体系结构 x86_64 clang 中找不到符号:错误:链接器命令失败，退出代码为 1(使用 -v 查看调用)。”实际上，这些消息直到我升级到 macOS Mojave 后才出现。

我得到的完整消息是:

g++ -Wall -fexceptions -g  -c /Users/suraj/Desktop/sfm/main.cpp -o obj/Debug/main.o
g++  -o bin/Debug/sfm obj/Debug/main.o   
Undefined symbols for architecture x86_64:
"sf::CircleShape::CircleShape(float, unsigned long)", referenced from:
  _main in main.o
"sf::RenderStates::Default", referenced from:
  _main in main.o
"sf::RenderTarget::draw(sf::Drawable const&, sf::RenderStates const&)", 
referenced from:
  _main in main.o
"sf::RenderTarget::clear(sf::Color const&)", referenced from:
  _main in main.o
"sf::RenderWindow::RenderWindow(sf::VideoMode, sf::String const&, 
 unsigned int, sf::ContextSettings const&)", referenced from:
  _main in main.o
"sf::RenderWindow::~RenderWindow()", referenced from:
  _main in main.o
"sf::Color::Green", referenced from:
  _main in main.o
"sf::Color::Color(unsigned char, unsigned char, unsigned char, unsigned 
char)", referenced from:
  _main in main.o
"sf::Shape::setFillColor(sf::Color const&)", referenced from:
  _main in main.o
"sf::Shape::~Shape()", referenced from:
  sf::CircleShape::~CircleShape() in main.o
"sf::String::String(char const*, std::__1::locale const&)", referenced 
from:
  _main in main.o
"sf::Window::close()", referenced from:
  _main in main.o
"sf::Window::display()", referenced from:
  _main in main.o
"sf::Window::pollEvent(sf::Event&)", referenced from:
  _main in main.o
"sf::VideoMode::VideoMode(unsigned int, unsigned int, unsigned int)", 
referenced from:
  _main in main.o
"sf::Window::isOpen() const", referenced from:
  _main in main.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)

代码是:

#include <SFML/Graphics.hpp>

int main()
{
sf::RenderWindow window(sf::VideoMode(400, 200), "SFML works!");
sf::CircleShape shape(100.f);
shape.setFillColor(sf::Color::Green);

while (window.isOpen())
{
    sf::Event event;
    while (window.pollEvent(event))
    {
        if (event.type == sf::Event::Closed)
            window.close();
    }

    window.clear();
    window.draw(shape);
    window.display();
}

return 0;
}

请帮忙。

Answer 1

更新答案 - 2019 年 5 月

openal 包似乎不再位于 homebrew 中，这导致下面的说明失败。我不知道这背后的背景。这是另一种方法。

您可以像这样找到 sfml 的所有 pkg-config 相关部分:

find /usr/local/Cellar/sfml -name \*pc

/usr/local/Cellar/sfml/2.5.1/lib/pkgconfig/sfml-network.pc
/usr/local/Cellar/sfml/2.5.1/lib/pkgconfig/sfml-all.pc
/usr/local/Cellar/sfml/2.5.1/lib/pkgconfig/sfml-graphics.pc
/usr/local/Cellar/sfml/2.5.1/lib/pkgconfig/sfml-audio.pc
/usr/local/Cellar/sfml/2.5.1/lib/pkgconfig/sfml-system.pc
/usr/local/Cellar/sfml/2.5.1/lib/pkgconfig/sfml-window.pc

在上面的列表中，你似乎不能使用 sfml-all 或 sfml-audio，所以你需要选择你想使用的部分并单独获取它们, 所以如果你想要 graphics, window 和 system:

pkg-config --libs --cflags sfml-graphics
-I/usr/local/Cellar/sfml/2.5.1/include 
-I/usr/local/opt/freetype/include/freetype2 
-I/usr/local/Cellar/sfml/2.5.1/include 
-L/usr/local/Cellar/sfml/2.5.1/lib -lsfml-graphics -lsfml-window -lsfml-system

pkg-config --libs --cflags sfml-system
-I/usr/local/Cellar/sfml/2.5.1/include 
-L/usr/local/Cellar/sfml/2.5.1/lib -lsfml-system

pkg-config --libs --cflags sfml-window
-I/usr/local/Cellar/sfml/2.5.1/include
-L/usr/local/Cellar/sfml/2.5.1/lib -lsfml-window -lsfml-system

因此，您将编译:

g++ main.cpp $(pkg-config --libs --cflags sfml-window sfml-system sfml-graphics) -o main

原始答案

如果您通过homebrew 安装了sfml，我建议您也像这样安装pkg-config:

brew install pkg-config

然后您可以获得编译所需的开关:

pkg-config --libs --cflags sfml-all

示例输出

-I/usr/local/Cellar/sfml/2.4.2_1/include -L/usr/local/Cellar/sfml/2.4.2_1/lib -lsfml-graphics -lsfml-window -lsfml-audio -lsfml-network -lsfml-system

所以你可以编译:

g++ main.cpp $(pkg-config --libs --cflags sfml-all) -o main