Compilation Steps - Breakdown

Compilation Steps

1. Preprocessing (cpp) cc -E a.c > a.i

# 1 "hello.c"

# 1 ""

# 1 ""

# 1 "/usr/include/stdc-predef.h" 1 3 4

# 1 "" 2

# 1 "hello.c"

..

...

extern void funlockfile (FILE *__stream) __attribute__ ((__nothrow__ , __leaf__));

# 943 "/usr/include/stdio.h" 3 4

# 2 "hello.c" 2

int main()

{

 printf("hello\n");

}

# 1 "/usr/include/x86_64-linux-gnu/bits/types.h" 1 3

2. Compilation (cc)    cc -S a.c            # generates a.s

extreme@ALOPRASA-EAN6Q:/mnt/c/Users/aloprasa/winlinux$ cat hello.s

        .file   "hello.c"

        .section        .rodata

.LC0:

        .string "hello"

        .text

        .globl  main

        .type   main, @function

main:

.LFB0:

        .cfi_startproc

        pushq   %rbp

        .cfi_def_cfa_offset 16

        .cfi_offset 6, -16

        movq    %rsp, %rbp

        .cfi_def_cfa_register 6

        movl    $.LC0, %edi

        call    puts

        popq    %rbp

        .cfi_def_cfa 7, 8

        ret

        .cfi_endproc

.LFE0:

        .size   main, .-main

        .ident  "GCC: (Ubuntu 4.8.4-2ubuntu1~14.04.3) 4.8.4"

        .section        .note.GNU-stack,"",@progbits

3. Assemble (as)       cc -c a.s            # a.o

extreme@ALOPRASA-EAN6Q:/mnt/c/Users/aloprasa/winlinux$ file hello.o

hello.o: ELF 64-bit LSB  relocatable, x86-64, version 1 (SYSV), not stripped

4. Linking (ld)        cc a.o -o a          # Generates binary program 'a'