What problems might the following macro bring to the application?

Question

Can the following macro bring problems?

#define sq(x) x*x

If yes, then how and why?please help.

Answer 1

All of these can cause trouble:

int x = 12;
int n = sq(x+3);
int y = sq(x++);
int z = 2 * sq(2 + n) * n;

comparared with a function sq.