Why comment parameter names rather than leave it as it is

Question

Sometimes I see code like this:

LRESULT OnPaint(UINT /*uMsg*/, WPARAM /*wParam*/, LPARAM /*lParam*/, BOOL& /*bHandled*/)

Why comment pa

Answer 1

Some compilers wouldn't issue a "unused argument warning" when you comment the argument or not provide it in the first place. But of course you would need to leave the type to have the correct signature.