C++ exe file won't update(Using Atom & MacOSX Terminal)

I'm using atom to write code in C++. When I compile my code in the terminal using g++ -Wall -std=c++14, it prints and compiles properly in the terminal. Any revisions to my code after the first print however, do not transfer over to my terminal, and when I run the same code, the original always prints. I'm saving my source code in atom everytime I make a revision. If I save the exe file in atom it becomes a binary and does not print anymore. Does anyone know how I can get my source code to update in my terminal when I save it? Any help would be great.