[expr.ass] Rename problematic stable label

As more folks from outside the technically focused WG21 committee
pay attention to our standard, some language starts to gain attention
as problematic.  This commit fixes one such case.

Author: AlisdairM

source/basic.tex

@@ -674,7 +674,7 @@
 is defined\iref{basic.def} or called\iref{expr.call}, or
 \item a class with a base class of type \tcode{T} is
 defined\iref{class.derived}, or
-\item an lvalue of type \tcode{T} is assigned to\iref{expr.ass}, or
+\item an lvalue of type \tcode{T} is assigned to\iref{expr.assign}, or
 \item the type \tcode{T} is the subject of an
 \keyword{alignof} expression\iref{expr.alignof}, or
 \item an \grammarterm{exception-declaration} has type \tcode{T}, reference to
@@ -3907,7 +3907,7 @@
 \end{itemize}
 If no initialization is performed for an object (including subobjects),
 such a byte retains its initial value
-until that value is replaced\iref{dcl.init.general,expr.ass}.
+until that value is replaced\iref{dcl.init.general,expr.assign}.
 If any bit in the value representation has an indeterminate value,
 the object has an indeterminate value;
 otherwise, if any bit in the value representation has an erroneous value,
@@ -3949,7 +3949,7 @@
   If an indeterminate or erroneous value of
   unsigned ordinary character type or \tcode{std::byte} type
   is produced by the evaluation of
-  the right operand of a simple assignment operator\iref{expr.ass}
+  the right operand of a simple assignment operator\iref{expr.assign}
   whose first operand is an lvalue of
   unsigned ordinary character type or \tcode{std::byte} type,
   an indeterminate value or that erroneous value, respectively, replaces

source/classes.tex

@@ -3117,7 +3117,7 @@
 Otherwise, $S(\mathtt{E})$ is empty.
 \end{itemize}
 In an assignment expression of the form \tcode{E1 = E2}
-that uses either the built-in assignment operator\iref{expr.ass}
+that uses either the built-in assignment operator\iref{expr.assign}
 or a trivial assignment operator\iref{class.copy.assign},
 for each element \tcode{X} of $S($\tcode{E1}$)$ and
 each anonymous union member \tcode{X}\iref{class.union.anon} that

source/compatibility.tex

@@ -2969,7 +2969,7 @@
 \howwide
 Rare.
 
-\diffref{expr.cond,expr.ass,expr.comma}
+\diffref{expr.cond,expr.assign,expr.comma}
 \indextext{conversion!lvalue-to-rvalue}%
 \indextext{rvalue!lvalue conversion to}%
 \indextext{lvalue}%

source/declarations.tex

@@ -1277,7 +1277,7 @@
 
 \pnum
 \indextext{const object!undefined change to}%
-Any attempt to modify\iref{expr.ass,expr.post.incr,expr.pre.incr} a
+Any attempt to modify\iref{expr.assign,expr.post.incr,expr.pre.incr} a
 const object\iref{basic.type.qualifier} during its
 lifetime\iref{basic.life} results in undefined behavior.
 \begin{example}
@@ -3007,7 +3007,7 @@
 \end{example}
 
 \pnum
-See also~\ref{expr.ass} and~\ref{dcl.init}.
+See also~\ref{expr.assign} and~\ref{dcl.init}.
 
 \pnum
 \begin{note}
@@ -5684,7 +5684,7 @@
 A reference cannot be changed to refer to another object after initialization.
 \indextext{assignment!reference}%
 \begin{note}
-Assignment to a reference assigns to the object referred to by the reference\iref{expr.ass}.
+Assignment to a reference assigns to the object referred to by the reference\iref{expr.assign}.
 \end{note}
 \indextext{argument passing!reference and}%
 Argument passing\iref{expr.call}
@@ -5939,7 +5939,7 @@
 \item as an argument to a constructor invocation\iref{dcl.init,expr.type.conv},
 \item as an initializer for a non-static data member\iref{class.mem},
 \item in a \grammarterm{mem-initializer}\iref{class.base.init}, or
-\item on the right-hand side of an assignment\iref{expr.ass}.
+\item on the right-hand side of an assignment\iref{expr.assign}.
 \end{itemize}
 
 \begin{example}

source/expressions.tex

@@ -131,7 +131,7 @@
 \begin{footnote}
 The cast and assignment operators must still perform their specific
 conversions as described in~\ref{expr.type.conv}, \ref{expr.cast},
-\ref{expr.static.cast} and~\ref{expr.ass}.
+\ref{expr.static.cast} and~\ref{expr.assign}.
 \end{footnote}
 
 \rSec1[expr.prop]{Properties of expressions}
@@ -297,7 +297,7 @@
 \begin{note}
 A program that attempts
 to modify an object through a nonmodifiable lvalue or through an rvalue
-is ill-formed\iref{expr.ass,expr.post.incr,expr.pre.incr}.
+is ill-formed\iref{expr.assign,expr.post.incr,expr.pre.incr}.
 \end{note}
 
 \pnum
@@ -4864,7 +4864,7 @@
 An operand with volatile-qualified type is deprecated;
 see~\ref{depr.volatile.type}.
 The expression \tcode{++x} is otherwise equivalent to \tcode{x+=1} and
-the expression \tcode{--x} is otherwise equivalent to \tcode{x-=1}\iref{expr.ass}.
+the expression \tcode{--x} is otherwise equivalent to \tcode{x-=1}\iref{expr.assign}.
 \begin{note}
 For postfix increment and decrement, see~\ref{expr.post.incr}.
 \end{note}
@@ -7296,7 +7296,7 @@
 \end{codeblock}
 \end{example}
 
-\rSec2[expr.ass]{Assignment and compound assignment operators}%
+\rSec2[expr.assign]{Assignment and compound assignment operators}%
 \indextext{expression!assignment and compound assignment}
 
 \pnum
@@ -7827,7 +7827,7 @@
 a \keyword{reinterpret_cast}\iref{expr.reinterpret.cast};
 
 \item
-a modification of an object\iref{expr.ass,expr.post.incr,expr.pre.incr}
+a modification of an object\iref{expr.assign,expr.post.incr,expr.pre.incr}
 unless it is applied to a non-volatile lvalue of literal type
 that refers to a non-volatile object
 whose lifetime began within the evaluation of $E$;

source/future.tex

@@ -73,7 +73,7 @@
 \pnum
 Certain assignments
 where the left operand is a volatile-qualified non-class type
-are deprecated; see~\ref{expr.ass}.
+are deprecated; see~\ref{expr.assign}.
 
 \begin{example}
 \begin{codeblock}

source/intro.tex

@@ -92,7 +92,7 @@
 Only glvalues of scalar type can be used to access objects.
 Reads of scalar objects are described in \ref{conv.lval} and
 modifications of scalar objects are described in
-\ref{expr.ass}, \ref{expr.post.incr}, and \ref{expr.pre.incr}.
+\ref{expr.assign}, \ref{expr.post.incr}, and \ref{expr.pre.incr}.
 Attempts to read or modify an object of class type
 typically invoke a constructor\iref{class.ctor}
 or assignment operator\iref{class.copy.assign};

source/overloading.tex

@@ -3093,7 +3093,7 @@
 \item
 an object or reference being initialized\iref{dcl.init,dcl.init.ref,dcl.init.list},
 \item
-the left side of an assignment\iref{expr.ass},
+the left side of an assignment\iref{expr.assign},
 \item
 a parameter of a function\iref{expr.call},
 \item

source/xrefdelta.tex

@@ -101,6 +101,9 @@
 % https://github.com/cplusplus/draft/pull/7345
 \movedxref{basic.stc.inherit}{basic.stc.general}
 
+% https://github.com/cplusplus/draft/pull/TBD
+\movedxref{expr.ass}{expr.assign}
+
 %%% Deprecated features.
 %%% Example:
 %