deferencing uninitialized pointer

Code:

---

void swap (int *x, int *y) {
    int *temp;
    *temp = *x;
    *x = *y;
    *y = *temp;
}

---

This code, as you know, has a good chance of crashing depending on where the temp pointer points to. My problem is to write a procedure that guarantees its crashing when run like this:

Code:

---

int main () {
    int a = 1, b = 2;
    proc(/* Some args might go here */);
    swap(&a, &b);
}

---

Any ideas?

Code:

---

void swap (int *x, int *y) {
    int *temp = 0;
    *temp = *x;
    *x = *y;
    *y = *temp;
}

---

That'll crash it every time for sure ;)

No no no, I'm asking about how to write a procedure 'proc', that when run in the 2nd segment of code, guarantees the deference in swap to crash.

Can't modify swap itself.

Why whould you want it to crash?
Just pass a NULL or invalid pointer as one of swap's parameters.

I refuse to answer this question based on its absurdity, and the fact that the only reason I can see to want to know such a thing is to write an exploit of some kind.
If that's not the case you'll have to exlpain your reasons and justify them too.

No idea why you'd want to, but passing NULL for either argument would probably be bad.

It's a purely academic question. The arguments to swap are fixed. A hint that I received is that proc should do something to the stack. The crash has to happen on deferencing temp, not the arguments to swap.

As such, it's not a C question, it's a question about the underlying architecture.