gcc -S

Example: Create the assembler code for a simple hello world proram

Here's a simple hello world program, written in C:

#include <stdio.h>

char buf[] = "Hello world";

int main() {
   puts(buf);
}

The following command creates the assembler code for the the program:

$ gcc -S -fno-asynchronous-unwind-tables  -masm=intel /tmp/hello-world.c -o /tmp/hello-world.S

Show the produced file:

$ cat /tm/hello-world.S
        .file   "hello-world.c"
        .intel_syntax noprefix
        .text
        .globl  buf
        .data
        .align 8
        .type   buf, @object
        .size   buf, 12
buf:
        .string "Hello world"
        .text
        .globl  main
        .type   main, @function
main:
        push    rbp
        mov     rbp, rsp
        lea     rdi, buf[rip]
        call    puts@PLT
        mov     eax, 0
        pop     rbp
        ret
        .size   main, .-main
        .ident  "GCC: (Debian 10.2.1-6) 10.2.1 20210110"
        .section        .note.GNU-stack,"",@progbits

I've used -fno-asynchronous-unwind-tables so that the .cfi_startproc, .cfi_def_cfa_offset, .cfi_def_cfa_register, .cfi_def_cfa and .cfi_endproc directives and the .LFB0 and .LFE0 labels won't be produced.

gcc -S

Example: Create the assembler code for a simple hello world proram

See also