Sublime Text 3 c++ undefined reference to classes

Question

I'm able to compile single file code but not anything with separate file classes. This works in code blocks, but not sublime text. I couldn't find any information on this topic so I'm asking here.

Here is my code (all in one folder):

main.cpp:

#include <iostream>
#include "Cat.h"

using namespace std;

int main()
{
  Cat c;

  cout << "Hello world!" << endl;
  return 0;
}

Cat.cpp:

#include <iostream>
#include "Cat.h"

using namespace std;

Cat::Cat()
{
  cout << "i am cat bboiii";
}

Cat.h:

#ifndef CAT_H
#define CAT_H


class Cat
{
    public:
        Cat();
};

#endif // CAT_H

Do you have a make file? How are you telling sublime (which by default just runs `make`) which files to compile? — Austin Mullins, Aug 18 '15 at 02:39

score 1 · Accepted Answer · edited May 23 '17 at 12:14

Your issue is most definitely with your Makefile. Whenever you split your code into header and source files you need to tell your compiler where to find those header files.

g++ -I/path/to/header Cat.cpp main.cpp -o Cat

The -I flag tells the compiler to include header files from the path you give it. If all your files are in one folder (which in your case they are), you can simply compile them as

g++ -I. Cat.cpp main.cpp -o Cat

where . stands for the current directory or

g++ Cat.cpp main.cpp -o Cat

as the compiler looks for headers in the current directory by default. As your project size grows, you will need to prepare your Makefile to automate the build process. The simplest Makefile would be

all:
   g++ Cat.cpp main.cpp -o Cat

and then you simply run make in the directory containing your makefile. I suggest you read this answer on how to make practical makefiles.

`-I.` does nothing. The compiler looks for header files in the current directory by default. — sepp2k, Aug 18 '15 at 03:20
True. I just added that for the sake of comprehension. Would edit to mention this as well. — romeric, Aug 18 '15 at 03:24

Sublime Text 3 c++ undefined reference to classes

main.cpp:

Cat.cpp:

Cat.h:

1 Answers1