None of those are true when using `==` either. The NaN example comes directly from IEEE754 The others are based on the fact that the two sides are not referri

None of those are true when using `==` either. The NaN example comes directly from IEEE754 The others are based on the fact that the two sides are not referring to the same object. C "equivalents" of your examples: int x[0], y[0]; x == y; // false typedef struct {} empty_t; empty_t *x, *y; x == y; // false int x[] = { 1 }, y[] = { 1 }; x == y; // false int x[] = { 0 }, y[] = { 0 }; x == y; // false