<html>
<head>
<base href="https://llvm.org/bugs/" />
</head>
<body><table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW --- - decltype of parenthesized xvalue does not correctly yield rvalue-reference"
href="https://llvm.org/bugs/show_bug.cgi?id=25055">25055</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>decltype of parenthesized xvalue does not correctly yield rvalue-reference
</td>
</tr>
<tr>
<th>Product</th>
<td>clang
</td>
</tr>
<tr>
<th>Version</th>
<td>3.7
</td>
</tr>
<tr>
<th>Hardware</th>
<td>All
</td>
</tr>
<tr>
<th>OS</th>
<td>All
</td>
</tr>
<tr>
<th>Status</th>
<td>NEW
</td>
</tr>
<tr>
<th>Severity</th>
<td>normal
</td>
</tr>
<tr>
<th>Priority</th>
<td>P
</td>
</tr>
<tr>
<th>Component</th>
<td>C++11
</td>
</tr>
<tr>
<th>Assignee</th>
<td>unassignedclangbugs@nondot.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>treh@think-cell.com
</td>
</tr>
<tr>
<th>CC</th>
<td>dgregor@apple.com, llvm-bugs@lists.llvm.org
</td>
</tr>
<tr>
<th>Classification</th>
<td>Unclassified
</td>
</tr></table>
<p>
<div>
<pre>The following code snippet contains the parenthesized decltype of an xvalue:
#include <type_traits>
struct Member {};
struct A { Member x; };
A MakeA();
static_assert(std::is_same<decltype((MakeA().x)), Member&&>::value, ""); //
MSVC++ 2015
//static_assert(std::is_same<decltype((MakeA().x)), Member>::value, ""); //
clang, gcc
The standard says in ยง7.1.6.2 about decltype(e)
(4.1) [...] unparenthesized case, does not apply here
(4.2) if e is an xvalue, decltype(e) is T&&, where T is the type of e;
This means clang and gcc are not standard-conformant.</pre>
</div>
</p>
<hr>
<span>You are receiving this mail because:</span>
<ul>
<li>You are on the CC list for the bug.</li>
</ul>
</body>
</html>