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    CWG Issue 803</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="803"></A><H4>803.
  
<TT>sizeof</TT> an enumeration type with a fixed underlying type
</H4>
<B>Section: </B>7.6.2.5&#160; [<A href="https://wg21.link/expr.sizeof">expr.sizeof</A>]
 &#160;&#160;&#160;

 <B>Status: </B>CD2
 &#160;&#160;&#160;

 <B>Submitter: </B>UK
 &#160;&#160;&#160;

 <B>Date: </B>3 March, 2009<BR><BR>


<A href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2010/n3086.html#UK70">N2800 comment
  UK&#160;70<BR></A>

<P>[Voted into WP at October, 2009 meeting.]</P>

<P>There is no reason for the prohibition of using <TT>sizeof</TT>
on &#8220;an enumeration type before all its enumerators have been
declared&#8221; (7.6.2.5 [<A href="https://wg21.link/expr.sizeof#1">expr.sizeof</A>] paragraph 1) if the
underlying type of the enumeration is fixed.</P>

<P><B>Proposed resolution (July, 2009):</B></P>

<P>Change 7.6.2.5 [<A href="https://wg21.link/expr.sizeof#1">expr.sizeof</A>] paragraph 1 as follows:</P>

<BLOCKQUOTE>

...The <TT>sizeof</TT> operator shall not be applied to an expression
that has function or incomplete type, or to an enumeration type
<INS>whose underlying type is not fixed</INS> before all its
enumerators have been declared, or to the parenthesized name of such
types, or to an lvalue that designates a bit-field...

</BLOCKQUOTE>

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