whatelse&then?nada.

main.c

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

bool sup;

void nada()
{
    if (!sup) printf("nada\n");
}

void what_else(bool then)
{
    sup = sup &then; //?
    return nada();
}

void main()
{
    sup = false;
    what_else(sup);
}