CWG2898 Clarify implicit conversion sequence from cv T to T

Editorial note: The new example is placed after an existing note,
even though the wording places it right after the added normative text.

Author: tkoeppe

source/overloading.tex

@@ -2126,24 +2126,13 @@
 defined for the purposes of \ref{over}; the actual initialization is
 defined in terms of constructors and is not a conversion.
 \end{note}
-Any difference in top-level cv-qualification is
-subsumed by the initialization itself and does not constitute a conversion.
-\begin{example}
-A parameter of type
-\tcode{A}
-can be initialized from an argument of type
-\tcode{const A}.
-The implicit conversion sequence for that case is the identity sequence; it
-contains no ``conversion'' from
-\tcode{const A}
-to
-\tcode{A}.
-\end{example}
 
 \pnum
-When the parameter has a class type and the argument expression has the
-same type, the implicit conversion sequence is an identity conversion.
+When the cv-unqualified version of the type of the argument expression
+is the same as the parameter type,
+the implicit conversion sequence is an identity conversion.
 When the parameter has a class type and the argument expression has a
+(possibly cv-qualified)
 derived class type, the implicit conversion sequence is a
 derived-to-base
 \indextext{conversion!derived-to-base}%
@@ -2153,6 +2142,14 @@
 There is no such standard conversion; this derived-to-base conversion exists
 only in the description of implicit conversion sequences.
 \end{note}
+\begin{example}
+An implicit conversion sequence from an argument of type \tcode{const A}
+to a parameter of type \tcode{A} can be formed,
+even if overload resolution for copy-initialization of \tcode{A}
+from the argument would not find a viable function\iref{over.match.ctor,over.match.viable}.
+The implicit conversion sequence for that case is the identity sequence; it
+contains no ``conversion'' from \tcode{const A} to \tcode{A}.
+\end{example}
 
 \pnum
 When the parameter is the implicit object parameter of a static member function,