Is it possible to set g++ to follow C++11 ISO (-std=c++11) through #define?

Question

I'm quite new to c++11 and I was wondering something...

I am using Code::Blocks and if I were to use c++11 in this IDE, i had to go to compiler settings, and and Check "Have g++ follow the C++11 ISO C++ language standard"

Is there any workaround so I can set a single .cpp file to use c++11 in the #define statement like this?

Note: This is a single "Build" file, NOT a project

By setting the compile option while not in project, it'll set it to Global Compile option that I prefer to not happen

I know that you can customize the build option in Project Files that It'll set c++11 for that project only

#include <iostream>

#define -std c++11

int main(){

    #if __cplusplus==201402L
        std::cout << "C++14" << std::endl;
    #elif __cplusplus==201103L
        std::cout << "C++11" << std::endl;
    #else
        std::cout << "C++" << std::endl;
    #endif
    return 0;
}

What I have found:

Changing #define __cplusplus 201103L is NOT a good idea, because it don't set the compiler to compile as c++11

Answer 1

Although I can see how it would be desirable for a source file to be self-documenting in this respect, this isn't possible.

The next best thing is to test conformance, as you've started to do:

#if __cplusplus < 201103L
#error This source must be compiled as C++11 or later
#endif

That ensures that compilation with a C++03 compiler will give a simple, understandable error message straight away.