Question

How do temporary objects get created during reference initialization by the compiler, and what does that mean?

EDIT

From the C++ standard:

12.2 Temporary objects [class.temporary] Temporaries of class type are created in various
contexts: binding a reference to a prvalue (8.5.3), returning 1 a
prvalue (6.6.3), a conversion that creates a prvalue (4.1, 5.2.9,
5.2.11, 5.4), throwing an exception (15.1), entering a handler (15.3), and in some initializations (8.5).

From this link: http://publib.boulder.ibm.com/infocenter/lnxpcomp/v8v101/index.jsp?topic=%2Fcom.ibm.xlcpp8l.doc%2Flanguage%2Fref%2Fcplr382.htm

When a temporary object is created to initialize a reference variable,
the name of the temporary object has the same scope as that of the
reference variable.

Answer 1

From your edit: 12.2 states that a temporary is created in the cases when you initialize a const reference where it refers to a prvalue. For example:

double d = 3.14;
const int &r = d;

the compiler transforms this code into something like this:

  int temp = d;         // creates a temporary int
  const int &r = temp;  // reference is bound to that temporary

The lifetime of temporary that is bound to a const reference is the lifetime of the reference. i.e. the temporary is destroyed when the reference goes out of the scope.