Question

I am trying to compile a game, but getting 100+ errors like:

C:\Users\AppData\Local\Temp\cctQCagR.o: In function `load_image(std::string)':
main.cpp:(.text+0x4bd4): undefined reference to `std::string::c_str() const'
C:\Users\Bill\AppData\Local\Temp\cctQCagR.o: In function `createShip(float, float)':
main.cpp:(.text+0x4da4): undefined reference to `std::allocator<char>::allocator()'
main.cpp:(.text+0x4dbc): undefined reference to `std::basic_string<char, std::char_tra
its<char>, std::allocator<char> >::basic_string(char const*, std::allocator<char> cons
t&)'
main.cpp:(.text+0x4de4): undefined reference to `std::basic_string<char, std::char_tra
its<char>, std::allocator<char> >::~basic_string()'
main.cpp:(.text+0x4e04): undefined reference to `std::basic_string<char, std::char_tra
its<char>, std::allocator<char> >::~basic_string()'
main.cpp:(.text+0x4e1c): undefined reference to `std::allocator<char>::~allocator()'
main.cpp:(.text+0x4e28): undefined reference to `std::allocator<char>::allocator()'
main.cpp:(.text+0x4e40): undefined reference to `std::basic_string<char, std::char_tra
its<char>, std::allocator<char> >::basic_string(char const*, std::allocator<char> cons
t&)'
main.cpp:(.text+0x4e60): undefined reference to `std::allocator<char>::~allocator()'
main.cpp:(.text+0x4e70): undefined reference to `__cxa_end_cleanup'
main.cpp:(.text+0x4e98): undefined reference to `std::basic_string<char, std::char_tra
its<char>, std::allocator<char> >::~basic_string()'
main.cpp:(.text+0x4eb8): undefined reference to `std::basic_string<char, std::char_tra
its<char>, std::allocator<char> >::~basic_string()'
main.cpp:(.text+0x4ed0): undefined reference to `std::allocator<char>::~allocator()'
main.cpp:(.text+0x4ef4): undefined reference to `std::allocator<char>::~allocator()'
main.cpp:(.text+0x4f04): undefined reference to `__cxa_end_cleanup'
C:\Users\Bill\AppData\Local\Temp\cctQCagR.o: In function `load_files()':
main.cpp:(.text+0x5164): undefined reference to `std::allocator<char>::allocator()'
main.cpp:(.text+0x517c): undefined reference to `std::basic_string<char, std::char_tra
its<char>, std::allocator<char> >::basic_string(char const*, std::allocator<char> cons
t&)'

Answer 1

I believe you’re trying to compile main.cpp with gcc instead of g++.

#include <string>
#include <stdio.h>
int main()
{
    std::string bla;
    bla = "BLA BLA";
    printf("%s\n",bla.c_str());
    return 0;
}

If you build the above code snippet with gcc you get the errors you mention.
If you use g++ it build ok, this makes sense since g++ will make sure all the proper stuff it put together when build C++.