A conversion-function may recurse infinitely.
          #2501   Compile-time warning
          A conversion-function may recurse infinitely.
Recovery
Compilation continues. The remainder of the conversion-function is parsed and code is generated anyway. At run-time, the conversion function may enter infinite recursion and cause an unrecoverable error.
Explanation
The body of a conversion-function should not manipulate an instance of the same type for which it was invoked in such a way as to re-invoke itself.