Merge 2025-11 CWG Motion 2

P3921R0 Core Language Working Group "ready" Issues for the November, 2025 meeting;
issues (non-DR) 2917, 2923, 3005, 3043, 3044, 3045, 3048, 3053, 3061, 3063, 3074, 3082, 3084,
3089, 3092, 3093, 3094, 3095, 3098, 3099, 3101, 3108, 3109, 3110, 3113, 3114, 3115, 3117, and 3118.

Author: tkoeppe

source/basic.tex

@@ -405,8 +405,9 @@
 an array operand, the set contains the potential results of that operand.
 \item If $E$ is a class member access
 expression\iref{expr.ref} of the form
-$E_1$ \tcode{.} \opt{\keyword{template}} $E_2$
-naming a non-static data member,
+$E_1$ \tcode{.} \opt{\keyword{template}} $E_2$,
+where $E_2$ designates a a non-static data member or
+a direct base class relationship,
 the set contains the potential results of $E_1$.
 \item If $E$ is a class member access expression
 naming a static data member,
@@ -1137,7 +1138,7 @@
 if its name is \tcode{_} (\unicode{005f}{low line}) and it declares
 \begin{itemize}
 \item
-a variable with automatic storage duration,
+a variable, other than a function parameter, with automatic storage duration,
 \item
 a structured binding
 %FIXME: "and" is strange below; maybe reword to something like:
@@ -1440,8 +1441,8 @@
 \grammarterm{compound-statement} of a \grammarterm{lambda-expression},
 \grammarterm{function-body}, or \grammarterm{function-try-block},
 \item
-substatement of a selection or iteration statement
-that is not itself a selection or iteration statement, or
+substatement of a selection, iteration, or expansion statement
+that is not itself a selection, iteration, or expansion statement, or
 \item
 \grammarterm{handler} of a \grammarterm{function-try-block}
 \end{itemize}
@@ -3272,6 +3273,8 @@
 \item
 an entity, value, or object that is TU-local,
 \item
+an annotation\iref{dcl.attr.annotation},
+\item
 a direct base class relationship $(D, B)$\iref{class.derived.general}
 for which either $D$ or $B$ is TU-local, or
 \item
@@ -3667,6 +3670,24 @@
 the address of an unspecified byte of storage
 occupied by the complete object of that subobject.
 
+\pnum
+The \defnx{constituent values}{constituent value} of an object $o$ are
+\begin{itemize}
+\item
+if $o$ has scalar type, the value of $o$;
+\item
+otherwise, the constituent values of any direct subobjects of $o$
+other than inactive union members.
+\end{itemize}
+The \defnx{constituent references}{constituent reference} of an object $o$ are
+\begin{itemize}
+\item
+any direct members of $o$ that have reference type, and
+\item
+the constituent references of any direct subobjects of $o$
+other than inactive union members.
+\end{itemize}
+
 \pnum
 Some operations are described as
 \defnx{implicitly creating objects}{object!implicit creation}
@@ -4909,24 +4930,32 @@
 \pnum
 The fourth context is when a temporary object
 is created in the \grammarterm{for-range-initializer} of
-either a range-based \keyword{for} statement
-or an enumerating expansion statement\iref{stmt.expand}.
+a range-based \keyword{for} statement.
 If such a temporary object would otherwise be destroyed
 at the end of the \grammarterm{for-range-initializer} full-expression,
 the object persists for the lifetime of the reference
 initialized by the \grammarterm{for-range-initializer}.
 
 \pnum
-The fifth context is when a temporary object is created
+The fifth context is when a temporary object is created in an element $E$
+of the \grammarterm{expansion-init-list}
+of an enumerating expansion statement\iref{stmt.expand}.
+If such a temporary object would otherwise be destroyed
+at the end of the full-expression of $E$,
+the object persists for the lifetime of the \grammarterm{for-range-declaration}
+initialized from $E$.
+
+\pnum
+The sixth context is when a temporary object is created
 in the \grammarterm{expansion-initializer}
-of an iterating or destructuring expansion statement.
+of a destructuring expansion statement.
 If such a temporary object would otherwise be destroyed
 at the end of that \grammarterm{expansion-initializer},
 the object persists for the lifetime of the reference
 initialized by the \grammarterm{expansion-initializer}, if any.
 
 \pnum
-The sixth context is when a temporary object
+The seventh context is when a temporary object
 is created in a structured binding declaration\iref{dcl.struct.bind}.
 Any temporary objects introduced by
 the \grammarterm{initializer}{s} for the variables
@@ -5304,9 +5333,17 @@
 layout-compatible standard-layout class types\iref{class.mem}.
 
 \pnum
-A type is \defn{consteval-only} if it is either
-\tcode{std::meta::info} or
-a type compounded from a consteval-only type\iref{basic.compound}.
+A type is \defn{consteval-only} if it is
+\begin{itemize}
+\item \tcode{std::meta::info},
+\item \cv{}~\tcode{T}, where \tcode{T} is a consteval-only type,
+\item a pointer or reference to a consteval-only type,
+\item an array of consteval-only type,
+\item a function type having a return type or any parameter type that is consteval-only,
+\item a class type with any non-static data member having consteval-only type, or
+\item a type ``pointer to member of class \tcode{C} of type \tcode{T}'',
+where at least one of \tcode{C} or \tcode{T} is a consteval-only type.
+\end{itemize}
 Every object of consteval-only type shall be
 \begin{itemize}
 \item
@@ -5317,6 +5354,8 @@
 an object whose lifetime begins and ends
 during the evaluation of a core constant expression.
 \end{itemize}
+Every function of consteval-only type shall be
+an immediate function\iref{expr.const}.
 
 \rSec2[basic.fundamental]{Fundamental types}
 
@@ -7024,13 +7063,6 @@
 observable behavior of the abstract machine.
 \end{example}
 
-\pnum
-\begin{note}
-Because of this and the preceding requirement regarding what threads of execution
-have to perform eventually, it follows that no thread of execution can execute
-forever without an execution step occurring.
-\end{note}
-
 \pnum
 A thread of execution \defnx{makes progress}{make progress!thread}
 when an execution step occurs or a

source/classes.tex

@@ -4187,8 +4187,9 @@
 \indextext{function!virtual|)}
 
 \pnum
-A \keyword{consteval} virtual function shall not override
-a virtual function that is not \keyword{consteval}.
+A class with a \keyword{consteval} virtual function that overrides
+a virtual function that is not \keyword{consteval}
+shall have consteval-only type\iref{basic.types.general}.
 A \keyword{consteval} virtual function shall not be overridden by
 a virtual function that is not \keyword{consteval}.
 
@@ -5179,7 +5180,8 @@
 \pnum
 An additional access check beyond those described earlier in \ref{class.access}
 is applied when a non-static data member or non-static member function is a
-protected member of its designating class\iref{class.access.base}.
+protected member of its designating class\iref{class.access.base}
+and is not designated by a \grammarterm{splice-expression}.
 \begin{footnote}
 This
 additional check does not apply to other members,
@@ -5188,9 +5190,11 @@
 As described earlier, access to a protected member is granted because the
 reference occurs in a friend or direct member of some class \tcode{C}. If the access is
 to form a pointer to member\iref{expr.unary.op}, the
-\grammarterm{nested-name-specifier} shall denote \tcode{C} or a class derived from
-\tcode{C}. All other accesses involve a (possibly implicit) object
-expression\iref{expr.ref}. In this case, the class of the object expression shall be
+\grammarterm{nested-name-specifier} shall designate \tcode{C} or a class derived from
+\tcode{C}.
+Otherwise, if the access involves a (possibly implicit)
+object expression\iref{expr.prim.id.general,expr.ref},
+the class of the object expression shall be
 \tcode{C} or a class derived from \tcode{C}.
 \begin{example}
 \begin{codeblock}

source/declarations.tex

@@ -5092,32 +5092,38 @@
 \end{itemize}
 
 \pnum
-A class type \tcode{T} is \defn{const-default-constructible} if
+A type \cv{}~\tcode{T} is \defn{const-default-constructible} if
+\begin{itemize}
+\item
+\tcode{T} is \tcode{std::meta::info};
+\item
+\tcode{T} is \tcode{std::nullptr_t};
+\item
 default-initialization of \tcode{T} would invoke
-a user-provided constructor of \tcode{T} (not inherited from a base class)
-or if
+a user-provided constructor of \tcode{T} (not inherited from a base class);
+\item
+\tcode{T} is a class type where
 \begin{itemize}
 \item
-each direct non-variant non-static data member \tcode{M} of \tcode{T}
-has a default member initializer
-or, if \tcode{M} is of class type \tcode{X} (or array thereof),
-\tcode{X} is const-default-constructible,
+each direct non-variant non-static data member of \tcode{T}
+has a default member initializer or
+is of const-default-constructible type,
 \item
 if \tcode{T} is a union with at least one non-static data member,
 exactly one variant member has a default member initializer,
 \item
 if \tcode{T} is not a union,
-for each anonymous union member with at least one non-static data member (if any),
-exactly one non-static data member has a default member initializer, and
+the type of each anonymous union member is const-default-constructible, and
+\item
+each potentially constructed base class of \tcode{T} is const-default-constructible; or
+\end{itemize}
 \item
-each potentially constructed base class of \tcode{T} is const-default-constructible.
+\tcode{T} is an array of const-default-constructible type.
 \end{itemize}
 
 If a program calls for the default-initialization of an object of a
 const-qualified type \tcode{T},
-\tcode{T} shall be \tcode{std::meta::\linebreak info}
-or a const-default-constructible class type,
-or array thereof.
+\tcode{T} shall be a const-default-constructible type.
 
 \pnum
 To
@@ -9804,6 +9810,9 @@
 the next statement shall be part of the same execution of
 the substatement of the innermost enclosing iteration statement.
 The program is ill-formed if there is no such statement.
+The innermost enclosing \tcode{switch} statement
+of a fallthrough statement $S$ shall be contained in
+the innermost enclosing expansion statement\iref{stmt.expand} of $S$, if any.
 
 \pnum
 \recommended
@@ -10209,14 +10218,15 @@
 \indextext{attribute!annotations}
 
 \pnum
-An annotation may be applied to any declaration of a
+An annotation may be applied
+to a \grammarterm{base-specifier} or
+to any declaration of a
 type,
 type alias,
 variable,
 function,
 namespace,
-enumerator,
-\grammarterm{base-specifier}, or
+enumerator, or
 non-static data member.
 
 \pnum