c++ - C++ 的 Hello World 错误

Question

我开始学习 C++，并尝试运行经典的 Hello World 程序:

#include <iostream>

using namespace std;

int main ()
{
  cout << "Hello, World!";
  return 0;
}

但是当我使用 GCC 在终端中编译它时，我总是会得到这个错误:

Undefined symbols for architecture x86_64:
  "std::basic_string<char, std::char_traits<char>, std::allocator<char> >::size() const", referenced from:
      std::__verify_grouping(char const*, unsigned long, std::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)in ccpe3DPY.o
  "std::basic_string<char, std::char_traits<char>, std::allocator<char> >::operator[](unsigned long) const", referenced from:
      std::__verify_grouping(char const*, unsigned long, std::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)in ccpe3DPY.o
  "std::cout", referenced from:
      _main in ccpe3DPY.o
  "std::basic_ostream<char, std::char_traits<char> >& std::operator<< <std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&, char const*)", referenced from:
      _main in ccpe3DPY.o
  "std::ios_base::Init::Init()", referenced from:
      __static_initialization_and_destruction_0(int, int)in ccpe3DPY.o
  "std::ios_base::Init::~Init()", referenced from:
      ___tcf_0 in ccpe3DPY.o
  "___gxx_personality_v0", referenced from:
      Dwarf Exception Unwind Info (__eh_frame) in ccpe3DPY.o
ld: symbol(s) not found for architecture x86_64
collect2: ld returned 1 exit status

你能告诉我为什么吗？

Answer 1

您已经使用 gcc 编译了您的程序，它是 C 编译器，而不是 C++ 编译器。使用 g++ 代替；它知道包含 C++ 运行时库，其中定义了那些缺失的符号。