首先，简单说明下问题情境，一共三个代码文件，一个主执行程序，两个动态库程序，结构与之前写的弱符号，weak symbol一致：
#include <string>
std::string g_name;
void init_name_lib1()
{
g_name = "lib1";
}
const char* get_name_lib1()
{
return g_name.c_str();
}
#include <string>
std::string g_name;
void init_name_lib2()
{
g_name = "lib2";
}
const char* get_name_lib2()
{
return g_name.c_str();
}
#include <iostream>
void init_name_lib1();
void init_name_lib2();
const char* get_name_lib1();
const char* get_name_lib2();
int main()
{
init_name_lib1();
init_name_lib2();
std::cout << "name from lib1: " << get_name_lib1() << std::endl;
std::cout << "name from lib2: " << get_name_lib2() << std::endl;
return EXIT_SUCCESS;
}