12 Overloading [over]

12.6 Overloaded operators [over.oper]

12.6.6 Class member access [over.ref]

operator-> shall be a non-static member function taking no parameters.
It implements the class member access syntax that uses ->.
postfix-expression -> template id-expression
An expression x->m is interpreted as (x.operator->())->m for a class object x of type T if T​::​operator->() exists and if the operator is selected as the best match function by the overload resolution mechanism ([over.match]).