Compiling multiple .cpp and .h files using g++. Am I doing it right?

Question

Lets say I have these files: main.cpp, ClassA.cpp, ClassA.h, ClassB.cpp, ClassB.h

• The main has #include "ClassA.h" and #include "ClassB.h" and each .cpp file includes its respective .h file. Is this correct?

Now I am compiling using g++ *.cpp after which I get an executable a.exe (Windows)

• And my question is that is this the right way? And lets say if I only make changes in one file (cpp or h)will this command also recompile the unchanged files(because I see no new files in the folder except a.exe)? Please explain. Also how do I prevent that?

P.S I am not familiar with make and do not want to use that either so please do not refer to that in the answers and I read Using G++ to compile multiple .cpp and .h files but I need more explanation regarding my questions.

Answer 1

If you want to do it manually, you can compile all your .cpp files into object files

g++ -c *.cpp

and link all the object files

g++ *.o -o a.out

If ClassA.cpp is changed, you can just recompile ClassA.cpp

g++ -c ClassA.cpp

and link them all again

g++ *.o -o a.out

At least, you do not need to recompile the unchanged .cpp files.

Answer 2

And my question is that is this the right way?

It will be better to create a makefile and use make to build your target.

And lets say if I only make changes in one file (cpp or h)will this command also recompile the unchanged files(because I see no new files in the folder except a.exe)?

Yes.

Please explain. Also how do I prevent that?

Using make. make will help keep track of dependencies and compile files that need to be compiled, or in general build targets that are out of date.