I prepared arrays in the initiated data segment:

This program cannot be compiled:

#include <u.h>
#include <libc.h>

uintptr frst[] = {nil, nil, nil, nil, nil};
uintptr scnd[] = {nil, nil, frst, &frst[1]};

void main(void) {
exits(nil);
}

...because of:

cpu% 5c t.c
t.c:5 initializer is not a constant: scnd

This program can be compiled:

#include <u.h>

#include <libc.h>

void* frst[] = {nil, nil, nil, nil, nil};
void* scnd[] = {nil, nil, frst, &frst[1]};

void main(void) {
exits(nil);
}

Pavel