Compile with gcc on -O2.

undefined.c

#include <stdio.h>
#include <limits.h>

int foo(int x) {
	return (x+1) > x;
}

int main(void) {
	printf("%d\n", (INT_MAX+1) > INT_MAX);
	printf("%d\n", foo(INT_MAX));
	return 0;
}