C++ Constructors have no return type. Just exactly

Question

I've Googled this and read many posts, but there are so many different answers that all make logical sense that I was wondering if an expert on the topic could demystify this question.

Some say that there is no return because there is no way to return - the syntax prohibits it - yes, this makes sense, but I believe that all functions have to return something, no? Others say that the constructor sort of returns the newly created object itself, which seems to make sense since the assignment operator is used on the constructor. Still others have other interesting explanations.

Answer 1

Constructors implicitly return an instance of the class itself. It will be contradicting if it were designed to return something and the programmer returned something completely different other than the class itself. Basically the syntax would be confusing.

Answer 2

but I believe that all functions have to return something, no?

No. What does it mean to return a value from a function? Well, the ABI for an implementation will specify that for some return type a function will set certain registers, or some memory at some offset from the stack pointer, to the value that is 'returned' by the function.

Obviously registers and memory exist and contain data after a constructor or void function is called, but the language says those functions don't return anything, and so the ABI doesn't specify which registers or memory to look in to find a return value. The code can't set a return value and calling code can get any return value.

So no, functions don't have to return anything.