Compilation in .c : What happens when you type gcc main.c?

First, we need to know the 4 steps of C compilation process

Components of Compiler

1. Preprocessor: Remove comments and include header files in source code, replace macro name with code

2. Compiler: Generate assembly code

3. Assembler: Convert assemble code into object code (the output is in binary)

4. Linker: Links with the libraries, codes and create an executable file, For example with a libraries.h + functions.c + main.c

Now let’s check a graphical example of a file compiling step per step in .c:

gcc

What is gcc?

GNU Compiler Collection”. GCC is an integrated distribution of compilers for several major programming languages. In language c, we will use ggc to compile our archives.

How we can use gcc?

We can use in different forms depending of what we want. You can search the commands that we need to add to gcc typing:

gcc - - help

manual that will appear when you use gcc — — help

Examples:

1. You want run ony the preprocessor for the file test.c

• First go to your manuall (gcc - - help) and search the option to preprocessor (-E)
• Then use with gcc

gcc -E test.c

2. And what happen if you want that the output of the file name will be: result

• Again, search in your manual and you will find “-o” . So add your “-o” before of the file that you want to apply. In this case, before “result” because, you want to create this file

gcc -E test,c -o result

3. Finally, let’s check one more example:

Advanced problem of the day: 101-quote.c

You can see that after compiling with

gcc -Wall 101-quote.c

it’s generate an automatic file a.out, and when we executed with:

./a.out

the program that we write inside of 101-quote.c runs, in this case is printing a phrase.

Now, you are an expert in gcc :) thank u for reading this post, you are amazing :D