How to pass “literal” integers by reference in C++ (Newbie)

Question

Edit: As many people have pointed out, pass-by-reference isn\'t generally appropriate as an optimisation for primitive types. This is excellent to know, so

Answer 1

Passing by reference is actually slower for such small values. To pass by reference, it is, under-the-hood, passing a pointer (which is an int-sized value anyway). Then, there is a hidden extra pointer indirection that is not free. It is more direct to simply pass the value.

Do this:

void fillRect( int x, int y, int width, int height )
{
    // do something
}

The compiler will most likely inline your function anyway, unless its big. So you wouldn't have been able to improve the performance by being "clever" in how you declared the function.