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    CWG Issue 2876</TITLE>
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<P><EM>This is an unofficial snapshot of the ISO/IEC JTC1 SC22 WG21
  Core Issues List revision 118b.
  See http://www.open-std.org/jtc1/sc22/wg21/ for the official
  list.</EM></P>
<P>2025-09-28</P>
<HR>
<A NAME="2876"></A><H4>2876.
  
Disambiguation of <TT>T x = delete("text")</TT>
</H4>
<B>Section: </B>9.6.1&#160; [<A href="https://wg21.link/dcl.fct.def.general">dcl.fct.def.general</A>]
 &#160;&#160;&#160;

 <B>Status: </B>CD7
 &#160;&#160;&#160;

 <B>Submitter: </B>Richard Smith
 &#160;&#160;&#160;

 <B>Date: </B>2024-03-22<BR>


<P>[Accepted at the June, 2024 meeting.]</P>



<P>P2573R2 (= delete("should have a reason");), adopted in Tokyo,
does not disambiguate the following syntax:</P>

<PRE>
  using T = void ();
  using U = int;

  T a = delete ("hello");
  U b = delete ("hello");
</PRE>

<P>Either may be parsed as a (semantically
ill-formed) <I>simple-declaration</I> whose initializer is
a <I>delete-expression</I> or as a <I>function-definition</I>.</P>

<P><B>Proposed resolution (approved by CWG 2024-05-31):</B></P>

<P>Change and split 9.1 [<A href="https://wg21.link/dcl.pre#9">dcl.pre</A>] paragraph 9 as follows:</P>

<BLOCKQUOTE>
<P class="ins">
An object definition causes storage of appropriate size and alignment
to be reserved and any appropriate initialization
(9.5 [<A href="https://wg21.link/dcl.init">dcl.init</A>]) to be done.
</P>

<P>
Syntactic components beyond those found in the general form
of <I>simple-declaration</I> are added to a function declaration to
make a <I>function-definition</I>.
<INS>A token sequence starting with <TT>{</TT> or <TT>=</TT> is
treated as a <I>function-body</I> (9.6.1 [<A href="https://wg21.link/dcl.fct.def.general">dcl.fct.def.general</A>]) if the
type of the <I>declarator-id</I> (9.3.4.1 [<A href="https://wg21.link/dcl.meaning.general">dcl.meaning.general</A>]) is a
function type, and is otherwise treated as
a <I>brace-or-equal-initializer</I> (9.5.1 [<A href="https://wg21.link/dcl.init.general">dcl.init.general</A>]).  [
Note: If the declaration acquires a function type through template
instantiation, the program is ill-formed; see
13.9.1 [<A href="https://wg21.link/temp.spec.general">temp.spec.general</A>].  The function type of a function
definition cannot be specified with a <I>typedef-name</I>
(9.3.4.6 [<A href="https://wg21.link/dcl.fct">dcl.fct</A>]). --end note ]</INS>
<DEL>An object declaration, however, is also a definition unless it
contains the extern specifier and has no initializer
(6.2 [<A href="https://wg21.link/basic.def">basic.def</A>]). An object definition causes storage of
appropriate size and alignment to be reserved and any appropriate
initialization (9.5 [<A href="https://wg21.link/dcl.init">dcl.init</A>]) to be done.</DEL>
</P>

</BLOCKQUOTE>

<P>This drafting also resolves <A HREF="2144.html">issue 2144</A>.</P>

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