Similar to the
-c flag, the
-S flag tells
gcc to compile the program and generate assembly code, which is basically a human-readable form of machine code.
$ gcc hello.c -S
The result is a file named
hello.s, which might look something like this:
.file "hello.c" .section .rodata .LC0: .string "Hello World" .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 movl $0, %eax popq %rbp .cfi_def_cfa 7, 8 ret .cfi_endproc .LFE0: .size main, .-main .ident "GCC: (Ubuntu/Linaro 4.7.3-1ubuntu1) 4.7.3" .section .note.GNU-stack,"",@progbits
gcc is usually configured to generate code for the machine you are running on, so for me it generates x86 assembly language, which runs on a wide variety of processors from Intel, AMD, and others. If you are running on a different architecture, you might see different code.