Linux From Scratch (LFS) is a project that provides you with
step-by-step instructions for building your own GNU/Linux OS
from source code. URL: http://www.linuxfromscratch.org/

One Day One Command
===================

gcc — GNU C Compiler

Summary:

Several versions of the compiler (C, C++, Objective-C, Ada, Fortran,
and Java) are integrated; this is why we use the name “GNU Compiler
Collection”. GCC can compile programs written in any of these above
languages.

This C program is used in the examples.

#define DISPLAY “Hello Worldn”
main()
{
 #ifdef MACRO
   printf(DISPLAY);
 #else
   printf(“No Macron”);
 #endif
}

Examples:

$ gcc hello.c — Place output in a.out file.

$ ./a.out — Run the binary file.

$ gcc -Wall hello.c — Show all warning messages.

$ gcc -c hello.c — Compile, Don’t Link. Place output in hello.o

$ gcc -S hello.c — Stop after the stage of compilation proper

                   and save the ASM code in hello.s file.

$ gcc -DMACRO hello.c — Predefine a Macro.

$ gcc -E hello.c — Stop after the preprocessing stage and print

                   output in stdout.

$ gcc hello.c -o hello — Place output in hello file.

$ ./hello — Run the binary file.

$ gcc -v hello.c -o hello — Show the details of compilation stages.

$ gcc -I./myIncludes/ hello.c — In myIncludes Dir also search for
                   
            the Header files.

Read: man or info gcc