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  26 <!--*************************************************************************-->
  27 <h1>C++ Support in Clang</h1>
  28 <!--*************************************************************************-->
  29 <p>Last updated: $Date: 2018-07-27 06:41:37 +0200 (Fri, 27 Jul 2018) $</p>
  30
  31 <p>Clang fully implements all published ISO C++ standards (<a
  32 href="#cxx98">C++98 / C++03</a>, <a
  33 href="#cxx11">C++11</a>, and <a
  34 href="#cxx14">C++14</a>), and most of the upcoming <a
  35 href="#cxx17">C++17</a> standard.
  36
  37 <p>The Clang community is continually striving to improve C++ standards
  38 compliance between releases by submitting and tracking <a
  39 href="cxx_dr_status.html">C++ Defect Reports</a> and implementing resolutions
  40 as they become available.</p>
  41
  42 <p>Experimental work is also under way to implement <a href="#ts">C++ Technical
  43 Specifications</a> that will help drive the future of the C++ programming
  44 language.</p>
  45
  46 <p>The <a href="http://llvm.org/bugs/">LLVM bug tracker</a> contains Clang
  47 C++ components that track known bugs with Clang's language conformance in
  48 each language mode.</p>
  49
  50 <h2 id="cxx98">C++98 implementation status</h2>
  51
  52 <p>Clang implements all of the ISO C++ 1998 standard
  53   (including the defects addressed in the ISO C++ 2003 standard)
  54   except for <tt>export</tt> (which was removed in C++11).
  55
  56 <h2 id="cxx11">C++11 implementation status</h2>
  57
  58 <p>Clang 3.3 and later implement all of the <a
  59   href="http://www.iso.org/standard/50372.html">ISO
  60   C++ 2011 standard</a>.
  61
  62 <p>By default, Clang builds C++ code according to the C++98 standard, with many
  63 C++11 features accepted as extensions. You can use Clang in C++11 mode with the
  64 <code>-std=c++11</code> option. Clang's C++11 mode can be used
  65 with <a href="http://libcxx.llvm.org/">libc++</a> or with gcc's libstdc++.
  66
  67 <details>
  68 <summary>List of features and minimum Clang version with support</summary>
  69
  70 <table width="689" border="1" cellspacing="0">
  71  <tr>
  72     <th>Language Feature</th>
  73     <th>C++11 Proposal</th>
  74     <th>Available in Clang?</th>
  75  </tr>
  76      <tr>
  77       <td>Rvalue references</td>
  78       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2006/n2118.html">N2118</a></td>
  79       <td class="full" align="center">Clang 2.9</td>
  80     </tr>
  81     <tr>
  82       <td>&nbsp;&nbsp;&nbsp;&nbsp;Rvalue references for <code>*this</code></td>
  83       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2439.htm">N2439</a></td>
  84       <td class="full" align="center">Clang 2.9</td>
  85     </tr>
  86     <tr>
  87       <td>Initialization of class objects by rvalues</td>
  88       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2004/n1610.html">N1610</a></td>
  89       <td class="full" align="center">Clang 2.9</td>
  90     </tr>
  91     <tr>
  92       <td>Non-static data member initializers</td>
  93       <td><a href="http://www.open-std.org/JTC1/SC22/WG21/docs/papers/2008/n2756.htm">N2756</a></td>
  94       <td class="full" align="center">Clang 3.0</td>
  95     </tr>
  96     <tr>
  97       <td>Variadic templates</td>
  98       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2242.pdf">N2242</a></td>
  99       <td class="full" align="center">Clang 2.9</td>
 100     </tr>
 101     <tr>
 102       <td>&nbsp;&nbsp;&nbsp;&nbsp;Extending variadic template template parameters</td>
 103       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2555.pdf">N2555</a></td>
 104       <td class="full" align="center">Clang 2.9</td>
 105     </tr>
 106     <tr>
 107       <td>Initializer lists</td>
 108       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2672.htm">N2672</a></td>
 109       <td class="full" align="center">Clang 3.1</td>
 110     </tr>
 111     <tr>
 112       <td>Static assertions</td>
 113       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2004/n1720.html">N1720</a></td>
 114       <td class="full" align="center">Clang 2.9</td>
 115     </tr>
 116     <tr>
 117       <td><code>auto</code>-typed variables</td>
 118       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2006/n1984.pdf">N1984</a></td>
 119       <td class="full" align="center">Clang 2.9</td>
 120     </tr>
 121     <tr>
 122       <td>&nbsp;&nbsp;&nbsp;&nbsp;Multi-declarator <code>auto</code></td>
 123       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2004/n1737.pdf">N1737</a></td>
 124       <td class="full" align="center">Clang 2.9</td>
 125     </tr>
 126     <tr>
 127       <td>&nbsp;&nbsp;&nbsp;&nbsp;Removal of auto as a storage-class specifier</td>
 128       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2546.htm">N2546</a></td>
 129       <td class="full" align="center">Clang 2.9</td>
 130     </tr>
 131     <tr>
 132       <td>&nbsp;&nbsp;&nbsp;&nbsp;New function declarator syntax</td>
 133       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2541.htm">N2541</a></td>
 134       <td class="full" align="center">Clang 2.9</td>
 135     </tr>
 136     <tr>
 137       <td rowspan="2">Lambda expressions</td>
 138       <td><a href="http://www.open-std.org/JTC1/SC22/WG21/docs/papers/2009/n2927.pdf">N2927</a></td>
 139       <td class="full" align="center">Clang 3.1</td>
 140     </tr>
 141       <tr>
 142         <!-- from Albuquerque 2017 -->
 143         <td><a href="http://wg21.link/p0588r1">P0588R1</a> (<a href="#dr">DR</a>)</td>
 144         <td class="none" align="center">No</td>
 145       </tr>
 146     <tr>
 147       <td>Declared type of an expression</td>
 148       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2343.pdf">N2343</a></td>
 149       <td class="full" align="center">Clang 2.9</td>
 150     </tr>
 151     <tr>
 152       <td>&nbsp;&nbsp;&nbsp;&nbsp;Incomplete return types</td>
 153       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2011/n3276.pdf">N3276</a></td>
 154       <td class="full" align="center">Clang 3.1</td>
 155     </tr>
 156     <tr>
 157       <td>Right angle brackets</td>
 158       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2005/n1757.html">N1757</a></td>
 159       <td class="full" align="center">Clang 2.9</td>
 160     </tr>
 161     <tr>
 162       <td>Default template arguments for function templates</td>
 163       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#226">DR226</a></td>
 164       <td class="full" align="center">Clang 2.9</td>
 165     </tr>
 166     <tr>
 167       <td>Solving the SFINAE problem for expressions</td>
 168       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2634.html">DR339</a></td>
 169       <td class="full" align="center">Clang 2.9</td>
 170     </tr>
 171     <tr>
 172       <td>Alias templates</td>
 173       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2258.pdf">N2258</a></td>
 174       <td class="full" align="center">Clang 3.0</td>
 175     </tr>
 176     <tr>
 177       <td>Extern templates</td>
 178       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2006/n1987.htm">N1987</a></td>
 179       <td class="full" align="center">Clang 2.9</td>
 180     </tr>
 181     <tr>
 182       <td>Null pointer constant</td>
 183       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2431.pdf">N2431</a></td>
 184       <td class="full" align="center">Clang 3.0</td>
 185     </tr>
 186     <tr>
 187       <td>Strongly-typed enums</td>
 188       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2347.pdf">N2347</a></td>
 189       <td class="full" align="center">Clang 2.9</td>
 190     </tr>
 191     <tr>
 192       <td>Forward declarations for enums</td>
 193       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2764.pdf">N2764</a>
 194       <br><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#1206">DR1206</a></td>
 195       <td class="full" align="center">Clang 3.1</td>
 196     </tr>
 197     <tr>
 198       <td>Standardized attribute syntax</td>
 199       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2761.pdf">N2761</a></td>
 200       <td class="full" align="center">Clang 3.3 <a href="#n2761">(1)</a></td>
 201     </tr>
 202     <tr>
 203       <td rowspan="2">Generalized constant expressions</td>
 204       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2235.pdf">N2235</a></td>
 205       <td class="full" align="center">Clang 3.1</td>
 206     </tr>
 207       <tr>
 208         <!-- from Albuquerque 2017 -->
 209         <td><a href="http://wg21.link/p0859r0">P0859R0</a> (<a href="#dr">DR</a>)</td>
 210         <td class="none" align="center">No</td>
 211       </tr>
 212     <tr>
 213       <td>Alignment support</td>
 214       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2341.pdf">N2341</a></td>
 215       <td class="full" align="center">Clang 3.3</td>
 216     </tr>
 217     <tr>
 218       <td>Conditionally-support behavior</td>
 219       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2004/n1627.pdf">N1627</a></td>
 220       <td class="full" align="center">Clang 2.9</td>
 221     </tr>
 222     <tr>
 223       <td>Changing undefined behavior into diagnosable errors</td>
 224       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2004/n1727.pdf">N1727</a></td>
 225       <td class="full" align="center">Clang 2.9</td>
 226     </tr>
 227     <tr>
 228       <td>Delegating constructors</td>
 229       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2006/n1986.pdf">N1986</a></td>
 230       <td class="full" align="center">Clang 3.0</td>
 231     </tr>
 232     <tr>
 233       <td rowspan="2">Inheriting constructors</td>
 234       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2540.htm">N2540</a></td>
 235       <td class="full" align="center">Clang 3.3</td>
 236     </tr>
 237       <tr>
 238         <!-- from Kona 2015 -->
 239         <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/p0136r1.html">P0136R1</a> (<a href="#dr">DR</a>)</td>
 240         <td class="full" align="center">Clang 3.9</td>
 241       </tr>
 242     <tr>
 243       <td>Explicit conversion operators</td>
 244       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2437.pdf">N2437</a></td>
 245       <td class="full" align="center">Clang 3.0</td>
 246     </tr>
 247     <tr>
 248       <td>New character types</td>
 249       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2249.html">N2249</a></td>
 250       <td class="full" align="center">Clang 2.9</td>
 251     </tr>
 252     <tr>
 253       <td>Unicode string literals</td>
 254       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2442.htm">N2442</a></td>
 255       <td class="full" align="center">Clang 3.0</td>
 256     </tr>
 257     <tr>
 258       <td>Raw string literals</td>
 259       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2442.htm">N2442</a></td>
 260       <td class="full" align="center">Clang 3.0</td>
 261     </tr>
 262     <tr>
 263       <td>Universal character names in literals</td>
 264       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2170.html">N2170</a></td>
 265       <td class="full" align="center">Clang 3.1</td>
 266     </tr>
 267     <tr>
 268       <td>User-defined literals</td>
 269       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2765.pdf">N2765</a></td>
 270       <td class="full" align="center">Clang 3.1</td>
 271     </tr>
 272     <tr>
 273       <td>Standard Layout Types</td>
 274       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2342.htm">N2342</a></td>
 275       <td class="full" align="center">Clang 3.0</td>
 276     </tr>
 277     <tr>
 278       <td>Defaulted functions</td>
 279       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2346.htm">N2346</a></td>
 280       <td class="full" align="center">Clang 3.0</td>
 281     </tr>
 282     <tr>
 283       <td>Deleted functions</td>
 284       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2346.htm">N2346</a></td>
 285       <td class="full" align="center">Clang 2.9</td>
 286     </tr>
 287     <tr>
 288       <td>Extended friend declarations</td>
 289       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2005/n1791.pdf">N1791</a></td>
 290       <td class="full" align="center">Clang 2.9</td>
 291     </tr>
 292     <tr>
 293       <td>Extending <code>sizeof</code></td>
 294       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2253.html">N2253</a>
 295       <br><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#850">DR850</a></td>
 296       <td class="full" align="center">Clang 3.1</td>
 297     </tr>
 298     <tr>
 299       <td>Inline namespaces</td>
 300       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2535.htm">N2535</a></td>
 301       <td class="full" align="center">Clang 2.9</td>
 302     </tr>
 303     <tr>
 304       <td>Unrestricted unions</td>
 305       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2544.pdf">N2544</a></td>
 306       <td class="full" align="center">Clang 3.1</td>
 307     </tr>
 308     <tr>
 309       <td>Local and unnamed types as template arguments</td>
 310       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm">N2657</a></td>
 311       <td class="full" align="center">Clang 2.9</td>
 312     </tr>
 313     <tr>
 314       <td rowspan="2">Range-based for</td>
 315       <td><a href="http://www.open-std.org/JTC1/SC22/WG21/docs/papers/2009/n2930.html">N2930</a></td>
 316       <td class="full" align="center">Clang 3.0</td>
 317     </tr>
 318       <tr>
 319         <!-- from Jacksonville 2018 -->
 320         <td><a href="http://wg21.link/p0962r1">P0962R1</a> (<a href="#dr">DR</a>)</td>
 321         <td class="none" align="center">No</td>
 322       </tr>
 323     <tr>
 324       <td>Explicit virtual overrides</td>
 325       <td><a href="http://www.open-std.org/JTC1/SC22/WG21/docs/papers/2009/n2928.htm">N2928</a>
 326       <br><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2010/n3206.htm">N3206</a>
 327       <br><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2011/n3272.htm">N3272</a></td>
 328       <td class="full" align="center">Clang 3.0</td>
 329     </tr>
 330     <tr>
 331       <td>Minimal support for garbage collection and reachability-based leak detection</td>
 332       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2670.htm">N2670</a></td>
 333       <td class="na" align="center">N/A <a href="#n2670">(2)</a></td>
 334     </tr>
 335     <tr>
 336       <td>Allowing move constructors to throw [noexcept]</td>
 337       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2010/n3050.html">N3050</a></td>
 338       <td class="full" align="center">Clang 3.0</td>
 339     </tr>
 340     <tr>
 341       <td>Defining move special member functions</td>
 342       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2010/n3053.html">N3053</a></td>
 343       <td class="full" align="center">Clang 3.0</td>
 344     </tr>
 345
 346     <tr class="separator">
 347       <th align="center" colspan="3">Concurrency</th>
 348     </tr>
 349     <tr>
 350       <td>Sequence points</td>
 351       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2239.html">N2239</a></td>
 352       <td class="full" align="center">Clang 3.3</td>
 353     </tr>
 354     <tr>
 355       <td>Atomic operations</td>
 356       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2427.html">N2427</a></td>
 357       <td class="full" align="center">Clang 3.1</td>
 358     </tr>
 359     <tr>
 360       <td>Strong Compare and Exchange</td>
 361       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2748.html">N2748</a></td>
 362       <td class="full" align="center">Clang 3.1 <a href="#n2748">(3)</a></td>
 363     </tr>
 364     <tr>
 365       <td>Bidirectional Fences</td>
 366       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2752.htm">N2752</a></td>
 367       <td class="full" align="center">Clang 3.1</td>
 368     </tr>
 369
 370     <tr>
 371       <td>Memory model</td>
 372       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2429.htm">N2429</a></td>
 373       <td class="full" align="center">Clang 3.2</td>
 374     </tr>
 375     <tr>
 376       <td>Data-dependency ordering: atomics and memory model</td>
 377       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2664.htm">N2664</a></td>
 378       <td class="full" align="center">Clang 3.2 <a href="#n2664">(4)</a></td>
 379     </tr>
 380     <tr>
 381       <td>Propagating exceptions</td>
 382       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2179.html">N2179</a></td>
 383       <td class="full" align="center">Clang 2.9</td>
 384     </tr>
 385     <tr>
 386       <td>Allow atomics use in signal handlers</td>
 387       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2547.htm">N2547</a></td>
 388       <td class="full" align="center">Clang 3.1</td>
 389     </tr>
 390     <tr>
 391       <td>Thread-local storage</td>
 392       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2659.htm">N2659</a></td>
 393       <td class="full" align="center">Clang 3.3 <a href="#n2659">(5)</a></td>
 394     </tr>
 395     <tr>
 396       <td>Dynamic initialization and destruction with concurrency</td>
 397       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2660.htm">N2660</a></td>
 398       <td class="full" align="center">Clang 2.9</td>
 399     </tr>
 400
 401     <tr class="separator">
 402       <th align="center" colspan="3">C99 Features in C++11</th>
 403     </tr>
 404     <tr>
 405       <td><code>__func__</code> predefined identifier</td>
 406       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2340.htm">N2340</a></td>
 407       <td class="full" align="center">Clang 2.9</td>
 408     </tr>
 409     <tr>
 410       <td>C99 preprocessor</td>
 411       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2004/n1653.htm">N1653</a></td>
 412       <td class="full" align="center">Clang 2.9</td>
 413     </tr>
 414     <tr>
 415       <td><code>long long</code></td>
 416       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2005/n1811.pdf">N1811</a></td>
 417       <td class="full" align="center">Clang 2.9</td>
 418     </tr>
 419     <tr>
 420       <td>Extended integral types</td>
 421       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2006/n1988.pdf">N1988</a></td>
 422       <td class="na" align="center">N/A <a href="#n1988">(6)</a></td>
 423     </tr>
 424 </table>
 425
 426 <p>
 427 <span id="n2761">(1): The <code>[[carries_dependency]]</code> attribute
 428 has no effect.</span><br>
 429 <span id="n2670">(2): No compiler changes are required for an implementation
 430 such as Clang that does not provide garbage collection.</span><br>
 431 <span id="n2748">(3): All compare-exchange operations are emitted as
 432 strong compare-exchanges.</span><br>
 433 <span id="n2664">(4): <code>memory_order_consume</code> is lowered to
 434 <code>memory_order_acquire</code>.</span><br>
 435 <span id="n2659">(5): <code>thread_local</code> support
 436 requires a C++ runtime library providing <code>__cxa_thread_atexit</code>, such
 437 as <a href="http://libcxxabi.llvm.org">libc++abi</a> 3.6 or later,
 438 or libsupc++ 4.8 or later.</span><br>
 439 <span id="n1988">(6): No compiler changes are required for an implementation
 440 such as Clang that does not provide any extended integer types.
 441 <code>__int128</code> is not treated as an extended integer type,
 442 because changing <code>intmax_t</code> would be an ABI-incompatible
 443 change.</span>
 444 </p>
 445 </details>
 446
 447 <h2 id="cxx14">C++14 implementation status</h2>
 448
 449 <p>Clang 3.4 and later implement all of the <a
 450     href="http://www.iso.org/standard/64029.html">ISO
 451     C++ 2014 standard</a>.
 452
 453 <p>You can use Clang in C++14 mode with the <code>-std=c++14</code> option
 454 (use <code>-std=c++1y</code> in Clang 3.4 and earlier).</p>
 455
 456 <details>
 457 <summary>List of features and minimum Clang version with support</summary>
 458
 459 <table width="689" border="1" cellspacing="0">
 460  <tr>
 461     <th>Language Feature</th>
 462     <th>C++14 Proposal</th>
 463     <th>Available in Clang?</th>
 464  </tr>
 465     <tr>
 466       <td>Tweak to certain C++ contextual conversions</td>
 467       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2012/n3323.pdf">N3323</a></td>
 468       <td class="full" align="center">Clang 3.4</td>
 469     </tr>
 470     <tr>
 471       <td>Binary literals</td>
 472       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2012/n3472.pdf">N3472</a></td>
 473       <td class="full" align="center">Clang 2.9</td>
 474     </tr>
 475     <tr>
 476       <td>decltype(auto)</td>
 477       <td rowspan=2 style="vertical-align:middle"><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3638.html">N3638</a></td>
 478       <td class="full" align="center">Clang 3.3</td>
 479     </tr>
 480     <tr>
 481       <td>Return type deduction for normal functions</td>
 482       <td class="full" align="center">Clang 3.4</td>
 483     </tr>
 484     <tr>
 485       <td>Initialized lambda captures</td>
 486       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3648.html">N3648</a></td>
 487       <td class="full" align="center">Clang 3.4</td>
 488     </tr>
 489     <tr>
 490       <td>Generic lambdas</td>
 491       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3649.html">N3649</a></td>
 492       <td class="full" align="center">Clang 3.4</td>
 493     </tr>
 494     <tr>
 495       <td>Variable templates</td>
 496       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3651.pdf">N3651</a></td>
 497       <td class="full" align="center">Clang 3.4</td>
 498     </tr>
 499     <tr>
 500       <td>Relaxing requirements on constexpr functions</td>
 501       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3652.html">N3652</a></td>
 502       <td class="full" align="center">Clang 3.4</td>
 503     </tr>
 504     <tr>
 505       <td>Member initializers and aggregates</td>
 506       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3653.html">N3653</a></td>
 507       <td class="full" align="center">Clang 3.3</td>
 508     </tr>
 509     <tr>
 510       <td>Clarifying memory allocation</td>
 511       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3664.html">N3664</a></td>
 512       <td class="full" align="center">Clang 3.4</td>
 513     </tr>
 514     <tr>
 515       <td><tt>[[deprecated]]</tt> attribute</td>
 516       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3760.html">N3760</a></td>
 517       <td class="full" align="center">Clang 3.4</td>
 518     </tr>
 519     <tr>
 520       <td>Single quotation mark as digit separator</td>
 521       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3781.pdf">N3781</a></td>
 522       <td class="full" align="center">Clang 3.4</td>
 523     </tr>
 524     <tr>
 525       <td>C++ Sized Deallocation</td>
 526       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3778.html">N3778</a></td>
 527       <td class="full" align="center">Clang 3.4 <a href="#n3778">(7)</a></td>
 528     </tr>
 529 </table>
 530
 531 <p>
 532 <span id="n3778">(7): In Clang 3.7 and later, sized deallocation is only enabled
 533 if the user passes the <code>-fsized-deallocation</code> flag. The user must
 534 supply definitions of the sized deallocation functions, either by providing them
 535 explicitly or by using a C++ standard library that does. <code>libstdc++</code>
 536 added these functions in version 5.0, and <code>libc++</code> added them in
 537 version 3.7.
 538 </span>
 539 </p>
 540 </details>
 541
 542 <h2 id="cxx17">C++17 implementation status</h2>
 543
 544 <p>Clang 5 and later implement all the features of the
 545 <a href="https://www.iso.org/standard/68564.html">ISO C++ 2017 standard</a>.
 546
 547 <p>You can use Clang in C++17 mode with the <code>-std=c++17</code> option
 548 (use <code>-std=c++1z</code> in Clang 4 and earlier).</p>
 549
 550 <details open>
 551 <summary>List of features and minimum Clang version with support</summary>
 552
 553 <table width="689" border="1" cellspacing="0">
 554  <tr>
 555     <th>Language Feature</th>
 556     <th>C++17 Proposal</th>
 557     <th>Available in Clang?</th>
 558  </tr>
 559     <!-- Issaquah 2014 papers -->
 560     <tr>
 561       <td><tt>static_assert</tt> with no message</td>
 562       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n3928.pdf">N3928</a></td>
 563       <td class="full" align="center">Clang 3.5</td>
 564     </tr>
 565     <!-- Rapperswil papers -->
 566     <tr>
 567       <td>Disabling trigraph expansion by default</td>
 568       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4086.html">N4086</a></td>
 569       <td class="full" align="center">Clang 3.5</td>
 570     </tr>
 571     <!--
 572     <tr>
 573       <td rowspan="2">Terse range-based for loops (removed from C++17)</td>
 574       <td rowspan="2"><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n3994.htm">N3994</a></td>
 575       <td class="none" align="center">Clang 3.5: Yes</td>
 576     </tr>
 577     <tr>
 578       <td class="svn" align="center">SVN: No</td>
 579     </tr>
 580     -->
 581     <tr>
 582       <td><tt>typename</tt> in a template template parameter</td>
 583       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4051.html">N4051</a></td>
 584       <td class="full" align="center">Clang 3.5</td>
 585     </tr>
 586     <tr>
 587       <td>New <tt>auto</tt> rules for direct-list-initialization
 588       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n3922.html">N3922</a></td>
 589       <td class="full" align="center">Clang 3.8 <a href="#n3922">(8)</a></td>
 590     </tr>
 591     <!-- Urbana papers -->
 592     <tr>
 593       <td rowspan="2">Fold expressions</td>
 594       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4295.html">N4295</a></td>
 595       <td class="full" align="center">Clang 3.6</td>
 596     </tr>
 597       <tr> <!-- from Jacksonville -->
 598         <td><a href="http://wg21.link/p0036r0">P0036R0</a></td>
 599         <td class="full" align="center">Clang 3.9</td>
 600       </tr>
 601     <tr>
 602       <td><tt>u8</tt> character literals</td>
 603       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4267.html">N4267</a></td>
 604       <td class="full" align="center">Clang 3.6</td>
 605     </tr>
 606     <tr>
 607       <td>Nested namespace definition</td>
 608       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4230.html">N4230</a></td>
 609       <td class="full" align="center">Clang 3.6</td>
 610     </tr>
 611     <tr>
 612       <td>Attributes for namespaces and enumerators</td>
 613       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4266.html">N4266</a></td>
 614       <td class="full" align="center">Clang 3.6</td>
 615     </tr>
 616     <tr>
 617       <td>Allow constant evaluation for all non-type template arguments</td>
 618       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4268.html">N4268</a></td>
 619       <td class="full" align="center">Clang 3.6</td>
 620     </tr>
 621     <!-- Kona papers -->
 622     <tr>
 623       <td>Remove deprecated <tt>register</tt> storage class</td>
 624       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/p0001r1.html">P0001R1</a></td>
 625       <td class="full" align="center">Clang 3.8</td>
 626     </tr>
 627     <tr>
 628       <td>Remove deprecated <tt>bool</tt> increment</td>
 629       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/p0002r1.html">P0002R1</a></td>
 630       <td class="full" align="center">Clang 3.8</td>
 631     </tr>
 632     <tr>
 633       <td>Make exception specifications part of the type system</td>
 634       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/p0012r1.html">P0012R1</a></td>
 635       <td class="full" align="center">Clang 4</td>
 636     </tr>
 637     <tr>
 638       <td><tt>__has_include</tt> in preprocessor conditionals</td>
 639       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/p0061.html">P0061R1</a></td>
 640       <td class="full" align="center">Yes</td>
 641     </tr>
 642     <!-- Jacksonville papers -->
 643     <tr>
 644       <td><tt>[[fallthrough]]</tt> attribute</td>
 645       <td><a href="http://wg21.link/p0188r1">P0188R1</a></td>
 646       <td class="full" align="center">Clang 3.9</td>
 647     </tr>
 648     <tr>
 649       <td><tt>[[nodiscard]]</tt> attribute</td>
 650       <td><a href="http://wg21.link/p0189r1">P0189R1</a></td>
 651       <td class="full" align="center">Clang 3.9</td>
 652     </tr>
 653     <tr>
 654       <td><tt>[[maybe_unused]]</tt> attribute</td>
 655       <td><a href="http://wg21.link/p0212r1">P0212R1</a></td>
 656       <td class="full" align="center">Clang 3.9</td>
 657     </tr>
 658     <tr>
 659       <td>Aggregate initialization of classes with base classes</td>
 660       <td><a href="http://wg21.link/p0017r1">P0017R1</a></td>
 661       <td class="full" align="center">Clang 3.9</td>
 662     </tr>
 663     <tr>
 664       <td><tt>constexpr</tt> lambda expressions</td>
 665       <td><a href="http://wg21.link/p0170r1">P0170R1</a></td>
 666       <td class="full" align="center">Clang 5</td>
 667     </tr>
 668     <tr>
 669       <td>Differing <tt>begin</tt> and <tt>end</tt> types in range-based <tt>for</tt></td>
 670       <td><a href="http://wg21.link/p0184r0">P0184R0</a></td>
 671       <td class="full" align="center">Clang 3.9</td>
 672     </tr>
 673     <tr>
 674       <td>Lambda capture of <tt>*this</tt></td>
 675       <td><a href="http://wg21.link/p0018r3">P0018R3</a></td>
 676       <td class="full" align="center">Clang 3.9</td>
 677     </tr>
 678     <tr>
 679       <td>Direct-list-initialization of <tt>enum</tt>s</td>
 680       <td><a href="http://wg21.link/p0138r2">P0138R2</a></td>
 681       <td class="full" align="center">Clang 3.9</td>
 682     </tr>
 683     <tr>
 684       <td>Hexadecimal floating-point literals</td>
 685       <td><a href="http://wg21.link/p0245r1">P0245R1</a></td>
 686       <td class="full" align="center">Yes</td>
 687     </tr>
 688     <!-- Oulu papers -->
 689     <tr>
 690       <td>Using attribute namespaces without repetition</td>
 691       <td><a href="http://wg21.link/p0028r4">P0028R4</a></td>
 692       <td class="full" align="center">Clang 3.9</td>
 693     </tr>
 694     <tr>
 695       <td>Dynamic memory allocation for over-aligned data</td>
 696       <td><a href="http://wg21.link/p0035r4">P0035R4</a></td>
 697       <td class="full" align="center">Clang 4</td>
 698     </tr>
 699     <tr>
 700       <td rowspan="4">Template argument deduction for class templates</td>
 701       <td><a href="http://wg21.link/p0091r3">P0091R3</a></td>
 702       <td rowspan="2" class="full" align="center">Clang 5</td>
 703     </tr>
 704       <tr> <!-- from Issaquah -->
 705         <td><a href="http://wg21.link/p0512r0">P0512R0</a></td>
 706       </tr>
 707       <tr>
 708         <!-- from Kona 2017 -->
 709         <td><a href="http://wg21.link/p0620r1">P0620R0</a> (<a href="#dr">DR</a>)</td>
 710         <td class="svn" align="center">SVN</td>
 711       </tr>
 712       <tr>
 713         <!-- from Toronto 2017 -->
 714         <td><a href="http://wg21.link/p0702r1">P0702R1</a> (<a href="#dr">DR</a>)</td>
 715         <td class="full" align="center">Clang 6</td>
 716       </tr>
 717     <tr>
 718       <td>Non-type template parameters with <tt>auto</tt> type</td>
 719       <td><a href="http://wg21.link/p0127r2">P0127R2</a></td>
 720       <td class="full" align="center">Clang 4</td>
 721     </tr>
 722     <tr>
 723       <td>Guaranteed copy elision</td>
 724       <td><a href="http://wg21.link/p0135r1">P0135R1</a></td>
 725       <td class="full" align="center">Clang 4</td>
 726     </tr>
 727     <tr>
 728       <td rowspan=2>Stricter expression evaluation order</td>
 729       <td><a href="http://wg21.link/p0145r3">P0145R3</a></td>
 730       <td class="full" align="center" rowspan=2>Clang 4 <a href="#p0145">(9)</a></td>
 731     </tr>
 732     <tr>
 733       <td><a href="http://wg21.link/p0400r0">P0400R0</a></td>
 734     </tr>
 735     <tr>
 736       <td>Requirement to ignore unknown attributes</td>
 737       <td><a href="http://wg21.link/p0283r2">P0283R2</a></td>
 738       <td class="full" align="center">Yes</td>
 739     </tr>
 740     <tr>
 741       <td><tt>constexpr</tt> <em>if-statement</em>s</td>
 742       <td><a href="http://wg21.link/p0292r2">P0292R2</a></td>
 743       <td class="full" align="center">Clang 3.9</td>
 744     </tr>
 745     <tr>
 746       <td>Inline variables</td>
 747       <td><a href="http://wg21.link/p0386r2">P0386R2</a></td>
 748       <td class="full" align="center">Clang 3.9</td>
 749     </tr>
 750     <tr>
 751       <td rowspan="3">Structured bindings</td>
 752       <td><a href="http://wg21.link/p0217r3">P0217R3</a></td>
 753       <td class="full" align="center">Clang 4</td>
 754     </tr>
 755       <tr>
 756         <!-- from Jacksonville 2018 -->
 757         <td><a href="http://wg21.link/p0961r1">P0961R1</a> (<a href="#dr">DR</a>)</td>
 758         <td class="none" align="center">No</td>
 759       </tr>
 760       <tr>
 761         <!-- from Jacksonville 2018 -->
 762         <td><a href="http://wg21.link/p0969r0">P0969R0</a> (<a href="#dr">DR</a>)</td>
 763         <td class="none" align="center">No</td>
 764       </tr>
 765     <tr>
 766       <td>Separate variable and condition for <tt>if</tt> and <tt>switch</tt></td>
 767       <td><a href="http://wg21.link/p0305r1">P0305R1</a></td>
 768       <td class="full" align="center">Clang 3.9</td>
 769     </tr>
 770     <!-- Issaquah 2016 papers -->
 771     <tr>
 772       <td>Matching template template parameters to compatible arguments</td>
 773       <td><a href="http://wg21.link/p0522r0">P0522R0</a></td>
 774       <td class="partial" align="center">Partial <a href="#p0522">(10)</a></td>
 775     </tr>
 776     <tr>
 777       <td>Removing deprecated dynamic exception specifications</td>
 778       <td><a href="http://wg21.link/p0003r5">P0003R5</a></td>
 779       <td class="full" align="center">Clang 4</td>
 780     </tr>
 781     <tr>
 782       <td>Pack expansions in <em>using-declarations</em></td>
 783       <td><a href="http://wg21.link/p0195r2">P0195R2</a></td>
 784       <td class="full" align="center">Clang 4</td>
 785     </tr>
 786 </table>
 787
 788 <p>
 789 <span id="n3922">(8): This is a backwards-incompatible change that is applied to
 790 all language versions that allow type deduction from <tt>auto</tt>
 791 (per the request of the C++ committee).
 792 In Clang 3.7, a warning is emitted for all cases that would change meaning.
 793 </span><br>
 794 <span id="p0145">(9): Under the MS ABI, function parameters are destroyed from
 795 left to right in the callee. As a result, function parameters in calls to
 796 <tt>operator&lt;&lt;</tt>, <tt>operator&gt;&gt;</tt>, <tt>operator-&gt;*</tt>,
 797 <tt>operator&amp;&amp;</tt>, <tt>operator||</tt>, and <tt>operator,</tt>
 798 functions using expression syntax are no longer guaranteed to be destroyed in
 799 reverse construction order in that ABI.
 800 </span><br>
 801 <span id="p0522">(10): Despite being the resolution to a Defect Report, this
 802 feature is disabled by default in all language versions, and can be enabled
 803 explicitly with the flag <tt>-frelaxed-template-template-args</tt> in Clang 4
 804 onwards.
 805 The change to the standard lacks a corresponding change for template partial
 806 ordering, resulting in ambiguity errors for reasonable and previously-valid
 807 code. This issue is expected to be rectified soon.
 808 </span>
 809 </p>
 810 </details>
 811
 812 <h2 id="cxx20">C++2a implementation status</h2>
 813
 814 <p>Clang has <b>experimental</b> support for some proposed features of
 815 the C++ standard following C++17, provisionally named C++2a.
 816 Note that support for these features may change or be removed without notice,
 817 as the draft C++2a standard evolves.
 818
 819 <p>You can use Clang in C++2a mode with the <code>-std=c++2a</code> option.</p>
 820
 821 <details open>
 822 <summary>List of features and minimum Clang version with support</summary>
 823
 824 <table width="689" border="1" cellspacing="0">
 825  <tr>
 826     <th>Language Feature</th>
 827     <th>C++2a Proposal</th>
 828     <th>Available in Clang?</th>
 829  </tr>
 830     <!-- Toronto 2017 papers -->
 831     <tr>
 832       <td>Default member initializers for bit-fields</td>
 833       <td><a href="http://wg21.link/p0683r1">P0683R1</a></td>
 834       <td class="full" align="center">Clang 6</td>
 835     </tr>
 836     <tr>
 837       <td><tt>const&amp;</tt>-qualified pointers to members</td>
 838       <td><a href="http://wg21.link/p0704r1">P0704R1</a></td>
 839       <td class="full" align="center">Clang 6</td>
 840     </tr>
 841     <tr>
 842       <td>Allow <i>lambda-capture</i> <tt>[=, this]</tt></td>
 843       <td><a href="http://wg21.link/p0409r2">P0409R2</a></td>
 844       <td class="full" align="center">Clang 6</td>
 845     </tr>
 846     <tr>
 847       <td rowspan="2"><tt>__VA_OPT__</tt> for preprocessor comma elision</td>
 848       <td><a href="http://wg21.link/p0306r4">P0306R4</a></td>
 849       <td class="full" align="center">Clang 6</td>
 850     </tr>
 851       <tr> <!-- from Rapperswil -->
 852         <td><a href="http://wg21.link/p1042r1">P1042R1</a></td>
 853         <td class="partial" align="center">Partial</td>
 854       </tr>
 855     <tr>
 856       <td>Designated initializers</td>
 857       <td><a href="http://wg21.link/p0329r4">P0329R4</a></td>
 858       <td class="partial" align="center">Partial (extension)</td>
 859     </tr>
 860     <tr>
 861       <td><i>template-parameter-list</i> for generic lambdas</td>
 862       <td><a href="http://wg21.link/p0428r2">P0428R2</a></td>
 863       <td class="none" align="center">No</td>
 864     </tr>
 865     <tr id="p0734">
 866       <td rowspan="2">Concepts</td>
 867       <td><a href="http://wg21.link/p0734r0">P0734R0</a></td>
 868       <td rowspan="2" class="none" align="center">No</td>
 869     </tr>
 870       <tr> <!-- from Albuquerque -->
 871         <td><a href="http://wg21.link/p0857r0">P0857R0</a></td>
 872       </tr>
 873     <!-- Albuquerque papers -->
 874     <tr>
 875       <td>Range-based for statements with initializer</td>
 876       <td><a href="http://wg21.link/p0614r1">P0614R1</a></td>
 877       <td class="none" align="center">No</td>
 878     </tr>
 879     <tr>
 880       <td>ADL and function templates that are not visible</td>
 881       <td><a href="http://wg21.link/p0846r0">P0846R0</a></td>
 882       <td class="none" align="center">No</td>
 883     </tr>
 884     <tr>
 885       <td><tt>const</tt> mismatch with defaulted copy constructor</td>
 886       <td><a href="http://wg21.link/p0641r2">P0641R2</a></td>
 887       <td class="none" align="center">No</td>
 888     </tr>
 889     <tr>
 890       <td rowspan="3">Consistent comparison (<tt>operator&lt;=&gt;</tt>)</td>
 891       <td><a href="http://wg21.link/p0515r3">P0515R3</a></td>
 892       <td rowspan="3" class="partial" align="center">Partial</td>
 893     </tr>
 894       <tr> <!-- from Jacksonville -->
 895         <td><a href="http://wg21.link/p0905r1">P0905R1</a></td>
 896       </tr>
 897       <tr> <!-- from Rapperswil -->
 898         <td><a href="http://wg21.link/p1120r0">P1120R0</a></td>
 899       </tr>
 900     <tr>
 901       <td>Access checking on specializations</td>
 902       <td><a href="http://wg21.link/p0692r1">P0692R1</a></td>
 903       <td class="partial" align="center">Partial</td>
 904     </tr>
 905     <tr>
 906       <td>Default constructible and assignable stateless lambdas</td>
 907       <td><a href="http://wg21.link/p0624r2">P0624R2</a></td>
 908       <td class="none" align="center">No</td>
 909     </tr>
 910     <tr>
 911       <td>Lambdas in unevaluated contexts</td>
 912       <td><a href="http://wg21.link/p0315r4">P0315R4</a></td>
 913       <td class="none" align="center">No</td>
 914     </tr>
 915     <!-- Jacksonville papers -->
 916     <tr>
 917       <td><tt>[[no_unique_address]]</tt> attribute</td>
 918       <td><a href="http://wg21.link/p0840r2">P0840R2</a></td>
 919       <td class="none" align="center">No</td>
 920     </tr>
 921     <tr>
 922       <td><tt>[[likely]]</tt> and <tt>[[unlikely]]</tt> attributes</td>
 923       <td><a href="http://wg21.link/p0479r5">P0479R5</a></td>
 924       <td class="none" align="center">No</td>
 925     </tr>
 926     <tr>
 927       <td><tt>typename</tt> optional in more contexts</td>
 928       <td><a href="http://wg21.link/p0634r3">P0634R3</a></td>
 929       <td class="none" align="center">No</td>
 930     </tr>
 931     <tr>
 932       <td>Pack expansion in lambda <i>init-capture</i></td>
 933       <td><a href="http://wg21.link/p0780r2">P0780R2</a></td>
 934       <td class="none" align="center">No</td>
 935     </tr>
 936     <!-- Rapperswil papers -->
 937     <tr>
 938       <td>Class types as non-type template parameters</td>
 939       <td><a href="http://wg21.link/p0732r2">P0732R2</a></td>
 940       <td class="none" align="center">No</td>
 941     </tr>
 942     <tr>
 943       <td>Destroying operator delete</td>
 944       <td><a href="http://wg21.link/p0722r3">P0722R3</a></td>
 945       <td class="full" align="center">Clang 6</td>
 946     </tr>
 947     <tr>
 948       <td>Virtual function calls in constant expressions</td>
 949       <td><a href="http://wg21.link/p1064r0">P1064R0</a></td>
 950       <td class="none" align="center">No</td>
 951     </tr>
 952     <tr>
 953       <td>Prohibit aggregates with user-declared constructors</td>
 954       <td><a href="http://wg21.link/p1008r1">P1008R1</a></td>
 955       <td class="none" align="center">No</td>
 956     </tr>
 957     <tr>
 958       <td>Contracts</td>
 959       <td><a href="http://wg21.link/p0542r5">P0542R5</a></td>
 960       <td class="none" align="center">No</td>
 961     </tr>
 962     <tr>
 963       <td>Feature test macros</td>
 964       <td><a href="http://wg21.link/p0941r2">P0941R2</a></td>
 965       <td class="full" align="center"><a href="#sd6">(see below)</a></td>
 966     </tr>
 967     <tr>
 968       <td><tt>explicit(bool)</tt></td>
 969       <td><a href="http://wg21.link/p0892r2">P0892R2</a></td>
 970       <td class="none" align="center">No</td>
 971     </tr>
 972 </table>
 973 </details>
 974
 975 <h2 id="dr">Defect reports</h2>
 976
 977 <p>Clang generally aims to implement resolutions to Defect Reports (bug fixes
 978 against prior standards) retroactively, in all prior standard versions where
 979 the fix is meaningful. Significant Defect Report changes to language features
 980 after the publication of the relevant standard are marked (DR) in the above
 981 table.</p>
 982
 983 <p>Clang also has a test suite for conformance to resolutions for issues on the
 984 <a href="http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_toc.html">C++ core issues list</a>,
 985 most of which are considered Defect Reports.
 986 <a href="cxx_dr_status.html">Implementation status for C++ core issues</a> based on
 987 that test suite is tracked on a separate page.</p>
 988
 989 <h2 id="ts">Technical specifications and standing documents</h2>
 990
 991 <p>ISO C++ also publishes a number of documents describing additional language
 992 and library features that are not part of standard C++.</p>
 993
 994 <details open>
 995 <summary>List of features and minimum Clang version with support</summary>
 996
 997 <table width="689" border="1" cellspacing="0">
 998  <tr>
 999     <th>Document</th>
1000     <th>Latest draft</th>
1001     <th>Compiler flag</th>
1002     <th>Available in Clang?</th>
1003  </tr>
1004     <tr id="sd6">
1005       <td rowspan="5">SD-6: SG10 feature test recommendations</td>
1006       <td rowspan="5"><a href="http://isocpp.org/std/standing-documents/sd-6-sg10-feature-test-recommendations">SD-6</a></td>
1007       <td rowspan="5">N/A</td>
1008       <td class="full" align="center">
1009         Clang 3.4 (<a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3745">N3745</a>)</br>
1010       </td>
1011     </tr>
1012     <tr>
1013       <td class="full" align="center">
1014         Clang 3.6 (<a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4200">N4200</a>)</a>
1015       </td>
1016     </tr>
1017     <tr>
1018       <td class="full" align="center">
1019         Clang 4 (<a href="http://wg21.link/p0096r3">P0096R3</a>)</a>
1020       </td>
1021     </tr>
1022     <tr>
1023       <td class="full" align="center">
1024         Clang 5 (<a href="http://wg21.link/p0096r4">P0096R4</a>)</a>
1025       </td>
1026     </tr>
1027     <tr>
1028       <td class="svn" align="center">
1029         SVN (<a href="http://wg21.link/p0096r5">P0096R5</a>)</a>
1030       </td>
1031     </tr>
1032     <!-- FIXME: Implement latest recommendations.
1033     <tr>
1034       <td class="svn" align="center">
1035         SVN (<a href="http://wg21.link/p0096r3">P0096R3</a>)</a>
1036       </td>
1037     </tr>
1038     -->
1039     <!-- No compiler support is known to be needed for:
1040            * Concurrency TS
1041            * Parallelism TS (v1, v2)
1042            * Ranges TS
1043            * Networking TS
1044            * File System TS
1045     -->
1046     <tr>
1047       <td>[TS] Concepts</td>
1048       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/p0121r0.pdf">P0121R0</a></td>
1049       <td></td>
1050       <td class="na" align="center">Superseded by <a href="#p0734">P0734R0</a></td>
1051     </tr>
1052     <tr>
1053       <!-- track unimplemented Coroutines features: p0913r1 p0914r1 -->
1054       <td>[DRAFT TS] Coroutines</td>
1055       <td><a href="https://isocpp.org/files/papers/N4663.pdf">N4663</a></td>
1056       <td><tt>-fcoroutines-ts<br>-stdlib=libc++</tt></td>
1057       <td class="full" align="center">Clang 5</td>
1058     </tr>
1059     <tr>
1060       <td>[TS] Library Fundamentals, Version 1 (invocation type traits)</td>
1061       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4480.html">N4480</a></td>
1062       <td>N/A</td>
1063       <td class="none" align="center">No</td>
1064     </tr>
1065     <tr>
1066       <td>[TS] Library Fundamentals, Version 2 (<tt>source_location</tt>)</td>
1067      <td><a href="http://wg21.link/n4617">N4617</a></td>
1068       <td>N/A</td>
1069       <td class="none" align="center">No</td>
1070     </tr>
1071     <tr>
1072       <td>[TS] Modules</td>
1073       <td><a href="http://wg21.link/n4720">N4720</a></td>
1074       <td><tt>-fmodules-ts</tt></td>
1075       <td class="none" align="center">WIP</td>
1076     </tr>
1077     <tr>
1078       <td>[DRAFT TS] Reflection</td>
1079       <td><a href="http://wg21.link/n4746">N4746</a></td>
1080       <td></td>
1081       <td class="none" align="center">No</td>
1082     </tr>
1083     <tr>
1084       <td>[TS] Transactional Memory</td>
1085       <td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4514.pdf">N4514</a></td>
1086       <td></td>
1087       <td class="none" align="center">No</td>
1088     </tr>
1089 </table>
1090 </details>
1091
1092 </div>
1093 </body>
1094 </html>