Cross accumulated goto / labels.

[graphitemaster]

The following code doesn't compile

[[accumulate]] void main() {
    goto L2;
    :L1;
    print("hello world!\n");
    goto L3;
}

[[accumulate]] void main() {
    :L2;
    goto L1;
}

[[accumulate]] void main() {
    :L3;
}

It should be treated as

void main() {
    goto L2;
    :L1
    print("hello world!\n");
    goto L3;
    :L2
    goto L1;
    :L3
}

Which does compile

[graphitemaster]

this requires deferring global lookup until function is fully asssembled