ericbb

    push   rbp
    mov    rbp,rsp
    lea    rax,[rbp+0x10]
    mov    QWORD PTR [rbp+0x10],rax

    push   rbp
    mov    rbp,rsp
    sub    rsp,0x10
    mov    rax,rdi
    mov    rcx,rsi
    mov    rdx,rcx
    mov    QWORD PTR [rbp-0x10],rax
    mov    QWORD PTR [rbp-0x8],rdx
    lea    rax,[rbp-0x10]
    mov    QWORD PTR [rbp-0x10],rax

    #include <stdio.h>
    #include <stdlib.h>

    struct example { void *a, *b, *c; };

    void foo(struct example x)
    {
        x.a = &x;
        if (x.a != NULL) puts("In foo(), x.a is not NULL.");
    }

    int
    main(void)
    {
        struct example x = { .a = NULL };
        printf("sizeof(x): %lu bytes (%lu bits).\n", sizeof(x), 8 * sizeof(x));
        foo(x);
        if (x.a == NULL) puts("In main(), x.a is NULL.");
        return 0;
    }

    ff[x] = [atom[x] → x; T → ff[car[x]]]

    (defun ff (x) (cond ((atom x) x) (T (ff (car x)))))

    odd 0 = False
    odd n = even (n - 1)
    even 0 = True
    even n = odd (n - 1)

    $ cat test.c
    void _start(void)
    {
        __asm__(
            "movabsq $6278066737626506568,%rax\n\t"
            "movq %rax,-32(%rsp)\n\t"
            "movl $1684828783,-24(%rsp)\n\t"
            "movw $10,-20(%rsp)\n\t"
            "movq $1,%rax\n\t"
            "movq $1,%rdi\n\t"
            "leaq -32(%rsp),%rsi\n\t"
            "movq $13,%rdx\n\t"
            "syscall\n\t"
            "movq $60,%rax\n\t"
            "movq $0,%rdi\n\t"
            "syscall");
    }
    $ gcc -nostdlib -static -Os -o test test.c && strip test && ls -lgG test
    -rwxr-xr-x 1 864 Sep 28 14:22 test

    $ cat test.c
    static int sys_write(int fd, const void *buf, unsigned long n)
    {
        asm("mov $1,%rax; syscall");
    }
    
    static void sys_exit(int status)
    {
        asm("mov $60,%rax; syscall");
    }
    
    void _start(void)
    {
        char s[] = "Hello, World\n";
        int r = sys_write(1, s, sizeof(s) - 1);
        sys_exit(r == -1 ? 1 : 0);
    }
    $ gcc -nostdlib -static -o test test.c && ls -lgG test
    -rwxr-xr-x 1 1480 Sep 28 11:47 test

    void free_circularly_linked_list(struct node *head)
    {
      struct node *a = head->next;
      while (a != head) {
        struct node *b = a->next;
        free(a);
        a = b;
      }
      free(head);
    }