<HTML>
<HEAD>
<meta http-equiv="Content-Type" content="text/html; charset=us-ascii">
<TITLE>
    CWG Issue 860</TITLE>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<STYLE TYPE="text/css">
  INS { text-decoration:none; font-weight:bold; background-color:#A0FFA0 }
  .INS { text-decoration:none; background-color:#D0FFD0 }
  DEL { text-decoration:line-through; background-color:#FFA0A0 }
  .DEL { text-decoration:line-through; background-color: #FFD0D0 }
  @media (prefers-color-scheme: dark) {
    HTML { background-color:#202020; color:#f0f0f0; }
    A { color:#5bc0ff; }
    A:visited { color:#c6a8ff; }
    A:hover, a:focus { color:#afd7ff; }
    INS { background-color:#033a16; color:#aff5b4; }
    .INS { background-color: #033a16; }
    DEL { background-color:#67060c; color:#ffdcd7; }
    .DEL { background-color:#67060c; }
  }
  SPAN.cmnt { font-family:Times; font-style:italic }
</STYLE>
</HEAD>
<BODY>
<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="860"></A><H4>860.
  
Explicit qualification of constexpr member functions
</H4>
<B>Section: </B>9.2.6&#160; [<A href="https://wg21.link/dcl.constexpr">dcl.constexpr</A>]
 &#160;&#160;&#160;

 <B>Status: </B>C++11
 &#160;&#160;&#160;

 <B>Submitter: </B>Daniel Kr&#252;gler
 &#160;&#160;&#160;

 <B>Date: </B>6 April, 2009<BR>


<P>[Voted into WP at August, 2010 meeting.]</P>



<P>9.2.6 [<A href="https://wg21.link/dcl.constexpr#6">dcl.constexpr</A>] paragraph 6 says,</P>

<BLOCKQUOTE>

A constexpr specifier for a non-static member function that is not a
constructor declares that member function to be const (11.4.3 [<A href="https://wg21.link/class.mfct.non.static">class.mfct.non.static</A>]).

</BLOCKQUOTE>

<P>Is a <TT>const</TT> qualifier on such a member function redundant
or ill-formed?</P>

<P><B>Notes from the July, 2009 meeting:</B></P>

<P>The CWG agreed that a <TT>const</TT> qualifier on a constexpr
member function is simply redundant and not an error.</P>

<P><B>Proposed resolution (February, 2010):</B></P>

<P>Change 9.2.6 [<A href="https://wg21.link/dcl.constexpr#6">dcl.constexpr</A>] paragraph 6 as follows:</P>

<BLOCKQUOTE>

A <TT>constexpr</TT> specifier for a non-static member function
that is not a constructor declares that member function to be
<TT>const</TT> (11.4.3 [<A href="https://wg21.link/class.mfct.non.static">class.mfct.non.static</A>]). [<I>Note:</I> the
<TT>constexpr</TT> specifier has no other effect on the function
type. &#8212;<I>end note</I>] <INS>The keyword <TT>const</TT> is
ignored if it appears in the <I>cv-qualifier-seq</I> of the
function declarator of the declaration of such a member
function.</INS> The class of which that function is a member
shall be a literal type (6.9 [<A href="https://wg21.link/basic.types">basic.types</A>]). [<I>Example:</I>...

</BLOCKQUOTE>

<BR><BR>
</BODY>
</HTML>
