There are numerous posts complaining that "xintc.h" used in all interrupt examples is missing. There is "xscugic.h" appearing instead. Is there a way to get the "xintc.h" back or somehow make the "xscugic.h" work? None of the interrupt examples works on my Vivado 2017 because of this strange issue.
Finally I figured it out myself: most of the Vivado examples are for MicroBlaze with INTC core which is using the missing header file. Fortunately some of the examples support both (UART 16550 among them).