What happens when you type GCC main.c?

GCC stands for GNU Compiler Collections which is used to compile mainly C and C++ language.

Four Steps of Compilation: preprocessing, compiling, assembly, linking.

The different options of the GCC command allow the user to stop the compilation process at different stages.

#1- Preprocessing:

The preprocessor obeys commands that begin with # (known as directives) by removing comments, expanding macros, and expanding included files.

If you included a header file such as #include <stdio.h>, it will look for the stdio.h file and copy the header file into the source code file.

The preprocessor also generates macro code and replaces symbolic constants defined using #define with their values.

#2- Compiling:

It takes the output of the preprocessor and generates assembly language, an intermediate human readable language, specific to the target processor.

#3- Assembly:

The assembler (assembly language) converts the code into pure binary code (0 and 1).

#4- Linking:

If we are using a function from libraries, the linker will link our code with that library function code.