CWG2987 Remove dilapidated wording from static_cast

Author: tkoeppe

source/expressions.tex

@@ -4384,8 +4384,7 @@
 If \tcode{T} is an lvalue reference type
 or an rvalue reference to function type, the result is an lvalue;
 if \tcode{T} is an rvalue reference to object type, the result is an xvalue;
-otherwise, the result is a prvalue. The \keyword{static_cast} operator shall not cast
-away constness\iref{expr.const.cast}.
+otherwise, the result is a prvalue.
 
 \pnum
 \indextext{cast!static!reference}%
@@ -4474,36 +4473,11 @@
 \end{note}
 
 \pnum
-Otherwise,
-the inverse of a standard conversion sequence\iref{conv} not containing an
-lvalue-to-rvalue\iref{conv.lval},
-array-to-pointer\iref{conv.array},
-function-to-pointer\iref{conv.func},
-null pointer\iref{conv.ptr}, null member pointer\iref{conv.mem},
-boolean\iref{conv.bool}, or
-function pointer\iref{conv.fctptr}
-conversion, can be performed explicitly using \keyword{static_cast}. A
-program is ill-formed if it uses \keyword{static_cast} to perform the
-inverse of an ill-formed standard conversion sequence.
-\begin{example}
-\begin{codeblock}
-struct B { };
-struct D : private B { };
-void f() {
-  static_cast<D*>((B*)0);               // error: \tcode{B} is a private base of \tcode{D}
-  static_cast<int B::*>((int D::*)0);   // error: \tcode{B} is a private base of \tcode{D}
-}
-\end{codeblock}
-\end{example}
-
-\pnum
-The lvalue-to-rvalue\iref{conv.lval},
+Otherwise, the lvalue-to-rvalue\iref{conv.lval},
 array-to-pointer\iref{conv.array}, and
 function-to-pointer\iref{conv.func} conversions are applied to the
-operand. Such a \keyword{static_cast} is subject to the restriction that
-the explicit conversion does not cast away
-constness\iref{expr.const.cast}, and the following additional rules
-for specific cases:
+operand, and the conversions that can be performed using \keyword{static_cast} are listed below.
+No other conversion can be performed using \keyword{static_cast}.
 
 \pnum
 A value of a scoped enumeration type\iref{dcl.enum}
@@ -4619,9 +4593,6 @@
 \end{codeblock}
 \end{example}
 
-\pnum
-No other conversion can be performed using \keyword{static_cast}.
-
 \rSec3[expr.reinterpret.cast]{Reinterpret cast}
 
 \pnum