64 assembly output with gcc?

This question already has an answer here:

How to remove “noise” from GCC/clang assembly output? 3 answers

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The stuff that goes into .eh_frame section is unwind descriptors, which you only need to unwind stack (eg with GDB). While learning assembly, you could simply ignore it. Here is a way to do the "clean up" you want:

gcc -S -o - test.c | sed -e '/^.L/d' -e '/.eh_frame/Q'
        .file   "test.c"
        .text
.globl main
        .type   main,@function
main:
        pushq   %rbp
        movq    %rsp, %rbp
        movl    $0, %eax
        leave
        ret
        .size   main,.Lfe1-main

---

You can try placing the code you want to study in a function.

Eg:

int ftest(void)
{
    return 0;
}

int main(void)
{
    return ftest();
}

If you look at the assembly-source for test it will be as clean as you need.

..snip..
test:
.LFB2:
        pushq   %rbp
.LCFI0:
        movq    %rsp, %rbp
.LCFI1:
        movl    $0, %eax
        leave
        ret
..snip..

---

I've found that using the -Os flag makes things clearer. I tried it your tiny example, but it made very little difference.

That said, I remember it being helpful when I was learning assembly (on a Sparc).

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