`int` is the return type for `main()`

Reason

It's a language rule, but violated through "language extensions" so often that it is worth mentioning. Declaring main (the one global main of a program) void limits portability.

Example

    void main() { /* ... */ };  // bad, not C++

    int main()
    {
        std::cout << "This is the way to do it\n";
    }

Note

We mention this only because of the persistence of this error in the community. Note that despite its non-void return type, the main function does not require an explicit return statement.

Enforcement

• The compiler should do it
• If the compiler doesn't do it, let tools flag it