Is it OK to return a literal by const reference?

Question

Is this safe?

const int& f()
{
return 1;
}

What I'm trying to do is to return a some value to const &

Answer 1

It is not okay.
Returning reference to a temporary is not okay because accessing it outside the function causes Undefined Behavior.

Answer 2

No, you're returning a reference to a temporary variable - this is not safe. The temporary variable will have been destroyed upon function return.