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  26 <!--*************************************************************************-->
  27 <h1>C++ Support in Clang</h1>
  28 <!--*************************************************************************-->
  29
  30 <p>Clang implements the following published and upcoming ISO C++ standards:</p>
  31
  32 <table width="689" border="1" cellspacing="0">
  33  <tr>
  34   <th>Language Standard</th>
  35   <th>Flag</th>
  36   <th>Available in Clang?</th>
  37  </tr>
  38  <tr>
  39   <td><a href="#cxx26">C++2c</a></td>
  40   <td><tt>-std=c++2c</tt></td>
  41   <td class="partial" align="center">Partial</td>
  42  </tr>
  43 <tr>
  44   <td><a href="#cxx23">C++23</a></td>
  45   <td><tt>-std=c++23</tt></td>
  46   <td class="partial" align="center">Partial</td>
  47  </tr>
  48  <tr>
  49   <td><a href="#cxx20">C++20</a></td>
  50   <td><tt>-std=c++20</tt></td>
  51   <td class="partial" align="center">Partial</td>
  52  </tr>
  53  <tr>
  54   <td><a href="#cxx17">C++17</a></td>
  55   <td><tt>-std=c++17</tt></td>
  56   <td class="full" align="center">Clang 5</td>
  57  </tr>
  58  <tr>
  59   <td><a href="#cxx14">C++14</a></td>
  60   <td><tt>-std=c++14</tt></td>
  61   <td class="full" align="center">Clang 3.4</td>
  62  </tr>
  63  <tr>
  64   <td><a href="#cxx11">C++11</a></td>
  65   <td><tt>-std=c++11</tt></td>
  66   <td class="full" align="center">Clang 3.3</td>
  67  </tr>
  68  <tr>
  69   <td><a href="#cxx98">C++98 / C++03</a></td>
  70   <td><tt>-std=c++98</tt></td>
  71   <td class="full" align="center">Yes (other than <tt>export</tt>)</td>
  72 </tr>
  73 </table>
  74
  75 <p>The Clang community is continually striving to improve C++ standards
  76 compliance between releases by submitting and tracking <a
  77 href="cxx_dr_status.html">C++ Defect Reports</a> and implementing resolutions
  78 as they become available.</p>
  79
  80 <p>Experimental work is also under way to implement <a href="#ts">C++ Technical
  81 Specifications</a> that will help drive the future of the C++ programming
  82 language.</p>
  83
  84 <p>The <a href="https://github.com/llvm/llvm-project/issues/">LLVM bug tracker</a> uses
  85 the "c++" label, as well as mode-specific labels such as "c++11", "c++14",
  86 and so on, to track known bugs with Clang's language conformance.</p>
  87
  88 <h2 id="cxx26">C++2c implementation status</h2>
  89
  90 <!-- TODO add link to the ISO Standard after it's published. -->
  91 <p>Clang has support for some of the features of the C++ standard following
  92 C++23, informally referred to as C++26.</p>
  93
  94 <p>You can use Clang in C++2c mode with the <code>-std=c++2c</code> option.</p>
  95
  96 <details open>
  97 <summary>List of features and minimum Clang version with support</summary>
  98 <table width="689" border="1" cellspacing="0">
  99  <tr>
 100     <th>Language Feature</th>
 101     <th>C++26 Proposal</th>
 102     <th>Available in Clang?</th>
 103  </tr>
 104  <!-- Spring 2023 papers (Varna) -->
 105  <tr>
 106   <td>Remove undefined behavior from lexing</td>
 107   <td><a href="https://wg21.link/P2621R2">P2621R2</a> (<a href="#dr">DR</a>)</td>
 108   <td class="full" align="center">Clang 3.3</td>
 109  </tr>
 110  <tr>
 111   <td>Making non-encodable string literals ill-formed</td>
 112   <td><a href="https://wg21.link/P1854R4">P1854R4</a> (<a href="#dr">DR</a>)</td>
 113   <td class="full" align="center">Clang 14</td>
 114  </tr>
 115  <tr>
 116   <td>Unevaluated strings</td>
 117   <td><a href="https://wg21.link/P2361R6">P2361R6</a></td>
 118   <td class="unreleased" align="center">Clang 18</td>
 119  </tr>
 120  <tr>
 121   <td>Add @, $, and ` to the basic character set</td>
 122   <td><a href="https://wg21.link/P2558R2">P2558R2</a></td>
 123   <td class="full" align="center">Yes</td>
 124  </tr>
 125  <tr>
 126   <td>constexpr cast from <tt>void*</tt></td>
 127   <td><a href="https://wg21.link/P2738R1">P2738R1</a></td>
 128   <td class="full" align="center">Clang 17</td>
 129  </tr>
 130  <tr>
 131   <td>On the ignorability of standard attributes</td>
 132   <td><a href="https://wg21.link/P2552R3">P2552R3</a> (<a href="#dr">DR</a>)</td>
 133   <td class="none" align="center">No</td>
 134  </tr>
 135  <tr>
 136   <td>Static storage for braced initializers</td>
 137   <td><a href="https://wg21.link/P2752R3">P2752R3</a> (<a href="#dr">DR</a>)</td>
 138   <td class="none" align="center">No</td>
 139  </tr>
 140  <tr>
 141   <td>User-generated <tt>static_assert</tt> messages</td>
 142   <td><a href="https://wg21.link/P2741R3">P2741R3</a></td>
 143   <td class="full" align="center">Clang 17</td>
 144  </tr>
 145  <tr>
 146   <td>Placeholder variables with no name</td>
 147   <td><a href="https://wg21.link/P2169R4">P2169R4</a></td>
 148   <td class="unreleased" align="center">Clang 18</td>
 149  </tr>
 150 </table>
 151 </details>
 152
 153 <h2 id="cxx23">C++23 implementation status</h2>
 154
 155 <!-- TODO add link to the ISO Standard after it's published. -->
 156 <p>Clang has support for some of the features of the ISO C++ 2023 standard.</p>
 157
 158 <p>You can use Clang in C++23 mode with the <code>-std=c++23</code> option.</p>
 159
 160 <details open>
 161 <summary>List of features and minimum Clang version with support</summary>
 162
 163 <table width="689" border="1" cellspacing="0">
 164  <tr>
 165     <th>Language Feature</th>
 166     <th>C++23 Proposal</th>
 167     <th>Available in Clang?</th>
 168  </tr>
 169     <!-- Fall 2020 papers -->
 170     <tr>
 171       <td>Literal suffix <tt>uz</tt>, <tt>z</tt> for <tt>size_t</tt>, <tt>ssize_t</tt></td>
 172       <td><a href="https://wg21.link/p0330r8">P0330R8</a></td>
 173       <td class="full" align="center">Clang 13</td>
 174     </tr>
 175     <!-- Spring 2021 papers -->
 176     <tr>
 177       <td>Make <tt>()</tt> in lambdas optional in all cases</td>
 178       <td><a href="https://wg21.link/p1102r2">P1102R2</a></td>
 179       <td class="full" align="center">Clang 13</td>
 180     </tr>
 181     <tr>
 182       <td>Simpler implicit move</td>
 183       <td><a href="https://wg21.link/p2266r1">P2266R1</a></td>
 184       <td class="full" align="center">Clang 13</td>
 185     </tr>
 186     <tr>
 187       <td><tt>if consteval</tt></td>
 188       <td><a href="https://wg21.link/P1938R3">P1938R3</a></td>
 189       <td class="full" align="center">Clang 14</td>
 190     </tr>
 191     <tr>
 192       <td>Allow duplicate attributes</td>
 193       <td><a href="https://wg21.link/P2156R1">P2156R1</a></td>
 194       <td class="full" align="center">Clang 13</td>
 195     </tr>
 196     <tr>
 197       <td>Narrowing contextual conversions to bool</td>
 198       <td><a href="https://wg21.link/P1401R5">P1401R5</a></td>
 199       <td class="full" align="center">Clang 14</td>
 200     </tr>
 201     <tr>
 202       <td>Trimming whitespaces before line splicing</td>
 203       <td><a href="https://wg21.link/P2223R2">P2223R2</a></td>
 204       <td class="full" align="center">Yes</td>
 205     </tr>
 206     <tr>
 207       <td>Make declaration order layout mandated</td>
 208       <td><a href="https://wg21.link/p1847r4">P1874R4</a></td>
 209       <td class="full" align="center">Yes</td>
 210     </tr>
 211     <tr>
 212       <td>C++ identifier syntax using UAX 31</td>
 213       <td><a href="https://wg21.link/P1949R7">P1949R7</a></td>
 214       <td class="full" align="center">Clang 14</td>
 215     </tr>
 216     <tr>
 217       <td>Mixed string literal concatenation</td>
 218       <td><a href="https://wg21.link/p2201r1">P2201R1</a></td>
 219       <td class="full" align="center">Yes</td>
 220     </tr>
 221     <!-- October 2021 papers -->
 222     <tr>
 223       <td rowspan=2>Deducing this</td>
 224       <td><a href="https://wg21.link/P0847R7">P0847R7</a></td>
 225       <td class="unreleased" align="center">Clang 18</td>
 226     </tr>
 227     <tr>
 228       <td><a href="https://wg21.link/P2797R0">P2797R0</a></td>
 229       <td class="none" align="center">No</td>
 230     </tr>
 231     <tr>
 232       <td rowspan=2>Change scope of lambda trailing-return-type</td>
 233       <td><a href="https://wg21.link/P2036R3">P2036R3</a></td>
 234       <td rowspan=2 class="full" align="center">Clang 17</td>
 235     </tr>
 236     <tr>
 237       <td><a href="https://wg21.link/P2579R0">P2579R0</a></td>
 238     </tr>
 239     <tr>
 240       <td>Multidimensional subscript operator</td>
 241       <td><a href="https://wg21.link/P2128R6">P2128R6</a></td>
 242       <td class="full" align="center">Clang 15</td>
 243     </tr>
 244     <tr>
 245       <td>Non-literal variables (and labels and gotos) in constexpr functions</td>
 246       <td><a href="https://wg21.link/P2242R3">P2242R3</a></td>
 247       <td class="full" align="center">Clang 15</td>
 248     </tr>
 249     <tr>
 250       <td>Character encoding of diagnostic text</td>
 251       <td><a href="https://wg21.link/P2246R1">P2246R1</a></td>
 252       <td class="full" align="center">Yes</td>
 253     </tr>
 254     <tr>
 255       <td>Character sets and encodings</td>
 256       <td><a href="https://wg21.link/P2314R4">P2314R4</a></td>
 257       <td class="full" align="center">Yes</td>
 258     </tr>
 259     <tr>
 260       <td>Consistent character literal encoding</td>
 261       <td><a href="https://wg21.link/P2316R2">P2316R2</a></td>
 262       <td class="full" align="center">Yes</td>
 263     </tr>
 264     <tr>
 265       <td>Add support for preprocessing directives elifdef and elifndef</td>
 266       <td><a href="https://wg21.link/P2334R1">P2334R1</a></td>
 267       <td class="full" align="center">Clang 13</td>
 268     </tr>
 269     <tr>
 270       <td>Extend init-statement to allow alias-declaration</td>
 271       <td><a href="https://wg21.link/P2360R0">P2360R0</a></td>
 272       <td class="full" align="center">Clang 14</td>
 273     </tr>
 274     <tr>
 275       <td>auto(x): decay-copy in the language</td>
 276       <td><a href="https://wg21.link/P0849R8">P0849R8</a></td>
 277       <td class="full" align="center">Clang 15</td>
 278     </tr>
 279     <!-- February 2022 papers -->
 280     <tr>
 281       <td>Attributes on Lambda-Expressions</td>
 282       <td><a href="https://wg21.link/P2173R1">P2173R1</a></td>
 283       <td class="full" align="center">Clang 13</td>
 284     </tr>
 285     <tr>
 286       <td><tt>constexpr</tt> for <tt>&lt;cmath&gt;</tt> and <tt>&lt;cstdlib&gt;</tt></td>
 287       <td><a href="https://wg21.link/P0533R9">P0533R9</a></td>
 288       <td class="none" align="center">No</td>
 289     </tr>
 290     <tr>
 291       <td>Type trait to determine if a reference binds to a temporary</td>
 292       <td><a href="https://wg21.link/P2255R2">P2255R2</a></td>
 293       <td class="partial" align="center">
 294         <details><summary>Partial</summary>
 295           Clang provides <tt>__reference_constructs_from_temporary</tt> type
 296           trait builtin, with which <tt>std::reference_constructs_from_temporary</tt>
 297           is implemented. <tt>__reference_converts_from_temporary</tt> needs to be
 298           provided, following the normal cross-vendor convention to implement
 299           traits requiring compiler support directly.
 300         </details></td>
 301       </td>
 302     </tr>
 303     <!-- July 2022 papers -->
 304     <tr>
 305       <td>The Equality Operator You Are Looking For</td>
 306       <td><a href="https://wg21.link/P2468R2">P2468R2</a></td>
 307       <td class="full" align="center">Clang 16</td>
 308     </tr>
 309     <tr>
 310       <td>De-deprecating volatile compound operations</td>
 311       <td><a href="https://wg21.link/P2327R1">P2327R1</a></td>
 312       <td class="full" align="center">Clang 15</td>
 313     </tr>
 314     <tr>
 315       <td>Support for <code>#warning</code></td>
 316       <td><a href="https://wg21.link/P2437R1">P2437R1</a></td>
 317       <td class="full" align="center">Yes</td>
 318     </tr>
 319     <tr>
 320       <td>Remove non-encodable wide character literals and multicharacter wide character literals</td>
 321       <td><a href="https://wg21.link/P2362R3">P2362R3</a></td>
 322       <td class="full" align="center">Clang 14</td>
 323     </tr>
 324     <tr>
 325       <td>Labels at the end of compound statements</td>
 326       <td><a href="https://wg21.link/P2324R2">P2324R2</a></td>
 327       <td class="full" align="center">Clang 16</td>
 328     </tr>
 329     <tr>
 330       <td>Delimited escape sequences</td>
 331       <td><a href="https://wg21.link/P2290R3">P2290R3</a></td>
 332       <td class="full" align="center">Clang 15</td>
 333     </tr>
 334     <tr>
 335       <td>Named universal character escapes</td>
 336       <td><a href="https://wg21.link/P2071R2">P2071R2</a></td>
 337       <td class="full" align="center">Clang 15</td>
 338     </tr>
 339     <tr>
 340       <td>Relaxing some constexpr restrictions</td>
 341       <td><a href="https://wg21.link/P2448R2">P2448R2</a></td>
 342       <td class="partial" align="center">
 343         <details><summary>Clang 17 (Partial)</summary>
 344           We do not support outside of defaulted special memeber functions the change that constexpr functions no
 345           longer have to be constexpr compatible but rather support a less restricted requirements for constexpr
 346           functions. Which include allowing non-literal types as return values and parameters, allow calling of
 347           non-constexpr functions and constructors.
 348         </details></td>
 349       </td>
 350     </tr>
 351     <tr>
 352       <td>Using unknown pointers and references in constant expressions</td>
 353       <td><a href="https://wg21.link/P2280R4">P2280R4</a> (<a href="#dr">DR</a>)</td>
 354       <td class="none" align="center">No</td>
 355     </tr>
 356     <tr>
 357       <td>static <code>operator()</code></td>
 358       <td><a href="https://wg21.link/P1169R4">P1169R4</a></td>
 359       <td class="full" align="center">Clang 16</td>
 360     </tr>
 361     <tr>
 362       <td>Extended floating-point types and standard names</td>
 363       <td><a href="https://wg21.link/P1467R9">P1467R9</a></td>
 364       <td class="none" align="center">No</td>
 365     </tr>
 366     <tr>
 367       <td>Class template argument deduction from inherited constructors</td>
 368       <td><a href="https://wg21.link/P2582R1">P2582R1</a></td>
 369       <td class="none" align="center">No</td>
 370     </tr>
 371     <tr>
 372       <td>Portable assumptions</td>
 373       <td><a href="https://wg21.link/P1774R8">P1774R8</a></td>
 374       <td class="none" align="center">No</td>
 375     </tr>
 376     <tr>
 377       <td>Support for UTF-8 as a portable source file encoding</td>
 378       <td><a href="https://wg21.link/P2295R6">P2295R6</a></td>
 379       <td class="full" align="center">Clang 15</td>
 380     </tr>
 381     <tr>
 382       <td><code>char8_t</code> Compatibility and Portability Fix</td>
 383       <td><a href="https://wg21.link/P2513R3">P2513R3</a></td>
 384       <td class="full" align="center">Clang 16</td>
 385     </tr>
 386     <tr>
 387       <td>Relax requirements on <code>wchar_t</code> to match existing practices</td>
 388       <td><a href="https://wg21.link/P2460R2">P2460R2</a></td>
 389       <td class="full" align="center">Yes</td>
 390     </tr>
 391     <tr>
 392       <td>Explicit lifetime management</td>
 393       <td><a href="https://wg21.link/P2590R2">P2590R2</a></td>
 394       <td class="none" align="center">No</td>
 395     </tr>
 396     <!-- November 2022 (Kona) papers -->
 397     <tr>
 398       <td>static <code>operator[]</code></td>
 399       <td><a href="https://wg21.link/P2589R1">P2589R1</a></td>
 400       <td class="full" align="center">Clang 16</td>
 401     </tr>
 402     <tr>
 403       <td>Permitting static constexpr variables in constexpr functions</td>
 404       <td><a href="https://wg21.link/P2647R1">P2647R1</a></td>
 405       <td class="full" align="center">Clang 16</td>
 406     </tr>
 407     <tr>
 408       <td>consteval needs to propagate up</td>
 409       <td><a href="https://wg21.link/P2564R3">P2564R3</a> (<a href="#dr">DR</a>)</td>
 410       <td class="full" align="center">Clang 17</td>
 411     </tr>
 412     <tr>
 413       <td>Lifetime extension in range-based for loops</td>
 414       <td><a href="https://wg21.link/P2718R0">P2718R0</a></td>
 415       <td class="none" align="center">No</td>
 416     </tr>
 417     <!--Issaquah 2023 papers-->
 418     <tr>
 419       <td>Referencing The Unicode Standard</td>
 420       <td><a href="https://wg21.link/P2736R2">P2736R2</a></td>
 421       <td class="full" align="center">Yes</td>
 422     </tr>
 423 </table>
 424 </details>
 425
 426
 427 <h2 id="cxx20">C++20 implementation status</h2>
 428
 429 <p>Clang has support for some of the features of the
 430 <a href="https://www.iso.org/standard/79358.html">ISO C++ 2020 standard</a>.</p>
 431
 432 <p>You can use Clang in C++20 mode with the <code>-std=c++20</code> option
 433 (use <code>-std=c++2a</code> in Clang 9 and earlier).</p>
 434
 435 <details open>
 436 <summary>List of features and minimum Clang version with support</summary>
 437
 438 <table width="689" border="1" cellspacing="0">
 439  <tr>
 440     <th>Language Feature</th>
 441     <th>C++20 Proposal</th>
 442     <th>Available in Clang?</th>
 443  </tr>
 444     <!-- Toronto 2017 papers -->
 445     <tr>
 446       <td>Default member initializers for bit-fields</td>
 447       <td><a href="https://wg21.link/p0683r1">P0683R1</a></td>
 448       <td class="full" align="center">Clang 6</td>
 449     </tr>
 450     <tr>
 451       <td><tt>const&amp;</tt>-qualified pointers to members</td>
 452       <td><a href="https://wg21.link/p0704r1">P0704R1</a></td>
 453       <td class="full" align="center">Clang 6</td>
 454     </tr>
 455     <tr>
 456       <td>Allow <i>lambda-capture</i> <tt>[=, this]</tt></td>
 457       <td><a href="https://wg21.link/p0409r2">P0409R2</a></td>
 458       <td class="full" align="center">Clang 6</td>
 459     </tr>
 460     <tr>
 461       <td rowspan="2"><tt>__VA_OPT__</tt> for preprocessor comma elision</td>
 462       <td><a href="https://wg21.link/p0306r4">P0306R4</a></td>
 463       <td class="full" align="center">Clang 6</td>
 464     </tr>
 465       <tr> <!-- from Rapperswil -->
 466         <td><a href="https://wg21.link/p1042r1">P1042R1</a></td>
 467         <td class="full" align="center">Clang 9</td>
 468       </tr>
 469     <tr>
 470       <td>Designated initializers</td>
 471       <td><a href="https://wg21.link/p0329r4">P0329R4</a></td>
 472       <td class="full" align="center">Clang 10</td>
 473     </tr>
 474     <tr>
 475       <td><i>template-parameter-list</i> for generic lambdas</td>
 476       <td><a href="https://wg21.link/p0428r2">P0428R2</a></td>
 477       <td class="full" align="center">Clang 9</td>
 478     </tr>
 479     <tr id="p0734">
 480       <td rowspan="13">Concepts</td>
 481       <td><a href="https://wg21.link/p0734r0">P0734R0</a></td>
 482       <td class="full" align="center">Clang 10</td>
 483     </tr>
 484       <tr> <!-- from Albuquerque -->
 485         <td><a href="https://wg21.link/p0857r0">P0857R0</a></td>
 486         <td rowspan="1" class="full" align="center">Clang 16</td>
 487       </tr>
 488       <tr> <!-- from San Diego -->
 489         <td><a href="https://wg21.link/p1084r2">P1084R2</a></td>
 490         <td rowspan="2" class="full" align="center">Clang 10</td>
 491       </tr>
 492       <tr>
 493         <td><a href="https://wg21.link/p1141r2">P1141R2</a></td>
 494       </tr>
 495       <tr> <!-- from Cologne -->
 496         <td><a href="https://wg21.link/p0848r3">P0848R3</a></td>
 497         <td rowspan="1" class="partial" align="center">
 498           <details>
 499             <summary>Clang 16 (Partial)</summary>
 500             Because of other concepts implementation deficits, the __cpp_concepts macro is not yet set to 202002L.
 501             Also, the related defect reports <a href="https://wg21.link/cwg1496">DR1496</a> and
 502             <a href="https://wg21.link/cwg1734">DR1734</a> are not yet implemented. Accordingly, deleted
 503             special member functions are treated as eligible even though they shouldn't be.
 504           </details>
 505         </td>
 506         </tr>
 507       <tr>
 508         <td><a href="https://wg21.link/p1616r1">P1616R1</a></td>
 509         <td rowspan="2" class="full" align="center">Clang 10</td>
 510       </tr>
 511       <tr>
 512         <td><a href="https://wg21.link/p1452r2">P1452R2</a></td>
 513       </tr>
 514       <tr> <!-- from Belfast -->
 515         <td><a href="https://wg21.link/p1972r0">P1972R0</a></td>
 516         <td rowspan="4" class="full" align="center">Clang 10</td>
 517       </tr>
 518       <tr>
 519         <td><a href="https://wg21.link/p1980r0">P1980R0</a></td>
 520       </tr>
 521       <tr> <!-- from Prague -->
 522         <td><a href="https://wg21.link/p2103r0">P2103R0</a></td>
 523       </tr>
 524       <tr> <!-- from February 2022 -->
 525         <td><a href="https://wg21.link/p2493r0">P2493R0</a></td>
 526       </tr>
 527       <tr>
 528         <td><a href="https://wg21.link/p2092r0">P2092R0</a></td>
 529         <td rowspan="1" class="full" align="center">Clang 16</td>
 530       </tr>
 531       <tr>
 532         <td><a href="https://wg21.link/p2113r0">P2113R0</a></td>
 533         <td rowspan="1" class="full" align="center">Clang 16</td>
 534       </tr>
 535     <!-- Albuquerque papers -->
 536     <tr>
 537       <td>Range-based for statements with initializer</td>
 538       <td><a href="https://wg21.link/p0614r1">P0614R1</a></td>
 539       <td class="full" align="center">Clang 8</td>
 540     </tr>
 541     <tr>
 542       <td>ADL and function templates that are not visible</td>
 543       <td><a href="https://wg21.link/p0846r0">P0846R0</a></td>
 544       <td class="full" align="center">Clang 9</td>
 545     </tr>
 546     <tr>
 547       <td><tt>const</tt> mismatch with defaulted copy constructor</td>
 548       <td><a href="https://wg21.link/p0641r2">P0641R2</a></td>
 549       <td class="full" align="center">Clang 8</td>
 550     </tr>
 551     <tr>
 552       <td rowspan="10">Consistent comparison (<tt>operator&lt;=&gt;</tt>)</td>
 553       <td><a href="https://wg21.link/p0515r3">P0515R3</a></td>
 554       <td rowspan="8" class="full" align="center">Clang 10</td>
 555     </tr>
 556       <tr> <!-- from Jacksonville -->
 557         <td><a href="https://wg21.link/p0905r1">P0905R1</a></td>
 558       </tr>
 559       <tr> <!-- from Rapperswil -->
 560         <td><a href="https://wg21.link/p1120r0">P1120R0</a></td>
 561       </tr>
 562       <tr> <!-- from Kona 2019 -->
 563         <td><a href="https://wg21.link/p1185r2">P1185R2</a></td>
 564       </tr>
 565       <tr> <!-- from Cologne -->
 566         <td><a href="https://wg21.link/p1186r3">P1186R3</a></td>
 567       </tr>
 568       <tr>
 569         <td><a href="https://wg21.link/p1630r1">P1630R1</a></td>
 570       </tr>
 571       <tr> <!-- from Belfast -->
 572         <td><a href="https://wg21.link/p1946r0">P1946R0</a></td>
 573       </tr>
 574       <tr>
 575         <td><a href="https://wg21.link/p1959r0">P1959R0</a></td>
 576       </tr>
 577       <tr> <!-- from Prague -->
 578         <td><a href="https://wg21.link/p2002r1">P2002R1</a></td>
 579         <td class="full" align="center">Clang 17</td>
 580       </tr>
 581       <tr>
 582         <td><a href="https://wg21.link/p2085r0">P2085R0</a></td>
 583         <td class="full" align="center">Clang 14</td>
 584       </tr>
 585     <tr>
 586       <td>Access checking on specializations</td>
 587       <td><a href="https://wg21.link/p0692r1">P0692R1</a></td>
 588       <td class="full" align="center">Clang 14</td>
 589     </tr>
 590     <tr>
 591       <td>Default constructible and assignable stateless lambdas</td>
 592       <td><a href="https://wg21.link/p0624r2">P0624R2</a></td>
 593       <td class="full" align="center">Clang 8</td>
 594     </tr>
 595     <tr>
 596       <td>Lambdas in unevaluated contexts</td>
 597       <td><a href="https://wg21.link/p0315r4">P0315R4</a></td>
 598       <td class="full" align="center">Clang 17</td>
 599     </tr>
 600     <!-- Jacksonville papers -->
 601     <tr>
 602       <td><tt>[[no_unique_address]]</tt> attribute</td>
 603       <td><a href="https://wg21.link/p0840r2">P0840R2</a></td>
 604       <td class="full" align="center">Clang 9</td>
 605     </tr>
 606     <tr>
 607       <td><tt>[[likely]]</tt> and <tt>[[unlikely]]</tt> attributes</td>
 608       <td><a href="https://wg21.link/p0479r5">P0479R5</a></td>
 609       <td class="full" align="center">Clang 12</td>
 610     </tr>
 611     <tr>
 612       <td><tt>typename</tt> optional in more contexts</td>
 613       <td><a href="https://wg21.link/p0634r3">P0634R3</a></td>
 614       <td class="full" align="center">Clang 16</td>
 615     </tr>
 616     <tr>
 617       <td>Pack expansion in lambda <i>init-capture</i></td>
 618       <td><a href="https://wg21.link/p0780r2">P0780R2</a></td>
 619       <td class="full" align="center">Clang 9</td>
 620     </tr>
 621     <!-- Rapperswil papers -->
 622     <tr>
 623       <td rowspan="2">Class types as non-type template parameters</td>
 624       <td><a href="https://wg21.link/p0732r2">P0732R2</a></td>
 625       <td rowspan="2" class="partial" align="center">Partial</td>
 626     </tr>
 627       <tr> <!-- from Belfast -->
 628         <td><a href="https://wg21.link/p1907r1">P1907R1</a></td>
 629       </tr>
 630     <tr>
 631       <td>Destroying operator delete</td>
 632       <td><a href="https://wg21.link/p0722r3">P0722R3</a></td>
 633       <td class="full" align="center">Clang 6</td>
 634     </tr>
 635     <tr>
 636       <td rowspan="7">Relaxations of <tt>constexpr</tt> restrictions</td>
 637       <td><a href="https://wg21.link/p1064r0">P1064R0</a></td>
 638       <td class="full" align="center">Clang 9</td>
 639     </tr>
 640       <tr> <!-- from San Diego -->
 641         <td><a href="https://wg21.link/p1002r1">P1002R1</a></td>
 642         <td class="full" align="center">Clang 8</td>
 643       </tr>
 644       <tr>
 645         <td><a href="https://wg21.link/p1327r1">P1327R1</a></td>
 646         <td rowspan="2" class="full" align="center">Clang 9</td>
 647       </tr>
 648       <tr>
 649         <td><a href="https://wg21.link/p1330r0">P1330R0</a></td>
 650       </tr>
 651       <tr> <!-- from Cologne -->
 652         <td><a href="https://wg21.link/p1331r2">P1331R2</a></td>
 653         <td rowspan="3" class="full" align="center">Clang 10</td>
 654       </tr>
 655       <tr>
 656         <td><a href="https://wg21.link/p1668r1">P1668R1</a></td>
 657       </tr>
 658       <tr>
 659         <td><a href="https://wg21.link/p0784r7">P0784R7</a></td>
 660       </tr>
 661     <tr>
 662       <td>Prohibit aggregates with user-declared constructors</td>
 663       <td><a href="https://wg21.link/p1008r1">P1008R1</a></td>
 664       <td class="full" align="center">Clang 8</td>
 665     </tr>
 666     <tr>
 667       <td>Feature test macros</td>
 668       <td><a href="https://wg21.link/p0941r2">P0941R2</a></td>
 669       <td class="full" align="center"><a href="#sd6">(see below)</a></td>
 670     </tr>
 671     <tr>
 672       <td><tt>explicit(bool)</tt></td>
 673       <td><a href="https://wg21.link/p0892r2">P0892R2</a></td>
 674       <td class="full" align="center">Clang 9</td>
 675     </tr>
 676     <!-- San Diego papers -->
 677     <tr>
 678       <td>Signed integers are two's complement</td>
 679       <td><a href="https://wg21.link/p1236r1">P1236R1</a></td>
 680       <td class="full" align="center">Clang 9</td>
 681     </tr>
 682     <tr>
 683       <td><tt>char8_t</tt></td>
 684       <td><a href="https://wg21.link/p0482r6">P0482R6</a></td>
 685       <td class="full" align="center">Clang 7 <a href="#p0482">(11)</a></td>
 686     </tr>
 687     <tr>
 688       <td rowspan=2>Immediate functions (<tt>consteval</tt>)</td>
 689       <td><a href="https://wg21.link/p1073r3">P1073R3</a></td>
 690       <td class="full" align="center">Clang 17</td>
 691     </tr>
 692       <tr> <!-- from Prague -->
 693         <td><a href="https://wg21.link/p1937r2">P1937R2</a></td>
 694         <td class="full" align="center">Clang 14</td>
 695       </tr>
 696     <tr>
 697       <td><tt>std::is_constant_evaluated</tt></td>
 698       <td><a href="https://wg21.link/p0595r2">P0595R2</a></td>
 699       <td class="full" align="center">Clang 9</td>
 700     </tr>
 701     <tr>
 702       <td>Nested inline namespaces</td>
 703       <td><a href="https://wg21.link/p1094r2">P1094R2</a></td>
 704       <td class="full" align="center">Clang 8</td>
 705     </tr>
 706     <!-- Kona 2019 papers -->
 707     <tr>
 708       <td rowspan="2">Structured binding extensions</td>
 709       <td><a href="https://wg21.link/p1091r3">P1091R3</a></td>
 710       <td rowspan="2" class="full" align="center">Clang 16</td>
 711     </tr>
 712       <tr>
 713         <td><a href="https://wg21.link/p1381r1">P1381R1</a></td>
 714       </tr>
 715     <tr>
 716       <td rowspan="2">Stronger Unicode requirements</td>
 717       <td><a href="https://wg21.link/p1041r4">P1041R4</a></td>
 718       <td rowspan="2" class="full" align="center">Yes</td>
 719     </tr>
 720       <tr>
 721         <td><a href="https://wg21.link/p1139r2">P1139R2</a></td>
 722       </tr>
 723     <tr>
 724       <td rowspan="2">Parenthesized initialization of aggregates</td>
 725       <td><a href="https://wg21.link/p0960r3">P0960R3</a></td>
 726       <td rowspan="2" class="full" align="center">Clang 16</td>
 727     </tr>
 728       <tr> <!-- from Belfast -->
 729         <td><a href="https://wg21.link/p1975r0">P1975R0</a></td>
 730       </tr>
 731     <tr>
 732       <td rowspan="12">Modules</td>
 733       <td><a href="https://wg21.link/p1103r3">P1103R3</a></td>
 734       <td class="full" align="center">Clang 15</td>
 735     </tr>
 736       <tr> <!-- from Cologne -->
 737         <td><a href="https://wg21.link/p1766r1">P1766R1</a> (<a href="#dr">DR</a>)</td>
 738         <td class="full" align="center">Clang 11</td>
 739       </tr>
 740       <tr>
 741         <td><a href="https://wg21.link/p1811r0">P1811R0</a></td>
 742         <td class="none" align="center">No</td>
 743       </tr>
 744       <tr>
 745         <td><a href="https://wg21.link/p1703r1">P1703R1</a></td>
 746         <td class="none" align="center">Subsumed by P1857</td>
 747       </tr>
 748       <tr> <!-- from Belfast -->
 749         <td><a href="https://wg21.link/p1874r1">P1874R1</a></td>
 750         <td class="full" align="center">Clang 15</td>
 751       </tr>
 752       <tr> <!-- from Belfast -->
 753         <td><a href="https://wg21.link/p1979r0">P1979R0</a></td>
 754         <td class="none" align="center">No</td>
 755       </tr>
 756       <tr> <!-- from Prague -->
 757         <td><a href="https://wg21.link/p1779r3">P1779R3</a></td>
 758         <td class="full" align="center">Clang 15</td>
 759       </tr>
 760       <tr>
 761         <td><a href="https://wg21.link/p1857r3">P1857R3</a></td>
 762         <td class="none" align="center">No</td>
 763       </tr>
 764       <tr>
 765         <td><a href="https://wg21.link/p2115r0">P2115R0</a></td>
 766         <td class="partial" align="center">Partial</td>
 767       </tr>
 768       <tr>
 769         <td><a href="https://wg21.link/p1815r2">P1815R2</a></td>
 770         <td class="partial" align="center">Partial</td>
 771       </tr>
 772       <tr> <!-- from Kona 2022 -->
 773         <td><a href="https://wg21.link/P2615R1">P2615R1</a> (<a href="#dr">DR</a>)</td>
 774         <td class="none" align="center">No</td>
 775       </tr>
 776       <tr> <!-- from Issaquah 2023 -->
 777         <td><a href="https://wg21.link/P2788R0">P2788R0</a> (<a href="#dr">DR</a>)</td>
 778         <td class="none" align="center">No</td>
 779       </tr>
 780     <tr>
 781       <td>Coroutines</td>
 782       <td><a href="https://wg21.link/p0912r5">P0912R5</a></td>
 783       <td class="partial" align="center">
 784         <details><summary>Partial</summary>
 785           Fully supported on all targets except Windows, which
 786           still has some stability and ABI issues.
 787         </details></td>
 788     </tr>
 789     <!-- Cologne 2019 papers -->
 790     <tr>
 791       <td>Deprecate <tt>a[b,c]</tt></td>
 792       <td><a href="https://wg21.link/p1161r3">P1161R3</a></td>
 793       <td class="full" align="center">Clang 9</td>
 794     </tr>
 795     <tr>
 796       <td>Deprecate some problematic uses of <tt>volatile</tt></td>
 797       <td><a href="https://wg21.link/p1152r4">P1152R4</a></td>
 798       <td class="full" align="center">Clang 10</td>
 799     </tr>
 800     <tr>
 801       <td><tt>[[nodiscard("with reason")]]</tt></td>
 802       <td><a href="https://wg21.link/p1301r4">P1301R4</a></td>
 803       <td class="full" align="center">Clang 9</td>
 804     </tr>
 805     <tr>
 806       <td><tt>using enum</tt></td>
 807       <td><a href="https://wg21.link/p1099r5">P1099R5</a></td>
 808       <td class="full" align="center">Clang 13</td>
 809     </tr>
 810     <tr>
 811       <td rowspan=2>Class template argument deduction for aggregates</td>
 812       <td><a href="https://wg21.link/p1816r0">P1816R0</a></td>
 813       <td rowspan=2 class="full" align="center">Clang 17</td>
 814     </tr>
 815       <tr> <!-- from Prague -->
 816         <td><a href="https://wg21.link/p2082r1">P2082R1</a></td>
 817       </tr>
 818     <tr>
 819       <td>Class template argument deduction for alias templates</td>
 820       <td><a href="https://wg21.link/p1814r0">P1814R0</a></td>
 821       <td class="none" align="center">No</td>
 822     </tr>
 823     <tr>
 824       <td>Permit conversions to arrays of unknown bound</td>
 825       <td><a href="https://wg21.link/p0388r4">P0388R4</a></td>
 826       <td class="full" align="center">Clang 14</td>
 827     </tr>
 828     <tr>
 829       <td><tt>constinit</tt></td>
 830       <td><a href="https://wg21.link/p1143r2">P1143R2</a></td>
 831       <td class="full" align="center">Clang 10</td>
 832     </tr>
 833     <!-- Prague 2019 papers -->
 834     <tr>
 835       <td>Pseudo-destructors end object lifetimes</td>
 836       <td><a href="https://wg21.link/p0593r6">P0593R6</a> (<a href="#dr">DR</a>)</td>
 837       <td class="full" align="center">Clang 11</td>
 838     </tr>
 839     <tr>
 840       <td>More implicit moves</td>
 841       <td><a href="https://wg21.link/p1825r0">P1825R0</a> (<a href="#dr">DR</a>)</td>
 842       <td class="full" align="center">Clang 13</td>
 843     </tr>
 844 </table>
 845
 846 <p>
 847 <span id="p0482">(11): Prior to Clang 8, this feature is not enabled by
 848 <tt>-std=c++20</tt>, but can be enabled with <tt>-fchar8_t</tt>.
 849 </span>
 850 </p>
 851 </details>
 852
 853
 854 <h2 id="cxx17">C++17 implementation status</h2>
 855
 856 <p>Clang 5 and later implement all the features of the
 857 <a href="https://www.iso.org/standard/68564.html">ISO C++ 2017 standard</a>.</p>
 858
 859 <p>By default, Clang 16 or later builds C++ code according to the C++17 standard.
 860 You can use Clang in C++17 mode with the <code>-std=c++17</code> option
 861 (use <code>-std=c++1z</code> in Clang 4 and earlier).</p>
 862
 863 <details open>
 864 <summary>List of features and minimum Clang version with support</summary>
 865
 866 <table width="689" border="1" cellspacing="0">
 867  <tr>
 868     <th>Language Feature</th>
 869     <th>C++17 Proposal</th>
 870     <th>Available in Clang?</th>
 871  </tr>
 872     <!-- Issaquah 2014 papers -->
 873     <tr>
 874       <td><tt>static_assert</tt> with no message</td>
 875       <td><a href="https://wg21.link/n3928">N3928</a></td>
 876       <td class="full" align="center">Clang 3.5</td>
 877     </tr>
 878     <!-- Rapperswil papers -->
 879     <tr>
 880       <td>Disabling trigraph expansion by default</td>
 881       <td><a href="https://wg21.link/n4086">N4086</a></td>
 882       <td class="full" align="center">Clang 3.5</td>
 883     </tr>
 884     <tr>
 885       <td><tt>typename</tt> in a template template parameter</td>
 886       <td><a href="https://wg21.link/n4051">N4051</a></td>
 887       <td class="full" align="center">Clang 3.5</td>
 888     </tr>
 889     <tr>
 890       <td>New <tt>auto</tt> rules for direct-list-initialization
 891       <td><a href="https://wg21.link/n3922">N3922</a></td>
 892       <td class="full" align="center">Clang 3.8 <a href="#n3922">(8)</a></td>
 893     </tr>
 894     <!-- Urbana papers -->
 895     <tr>
 896       <td rowspan="2">Fold expressions</td>
 897       <td><a href="https://wg21.link/n4295">N4295</a></td>
 898       <td class="full" align="center">Clang 3.6</td>
 899     </tr>
 900       <tr> <!-- from Jacksonville -->
 901         <td><a href="https://wg21.link/p0036r0">P0036R0</a></td>
 902         <td class="full" align="center">Clang 3.9</td>
 903       </tr>
 904     <tr>
 905       <td><tt>u8</tt> character literals</td>
 906       <td><a href="https://wg21.link/n4267">N4267</a></td>
 907       <td class="full" align="center">Clang 3.6</td>
 908     </tr>
 909     <tr>
 910       <td>Nested namespace definition</td>
 911       <td><a href="https://wg21.link/n4230">N4230</a></td>
 912       <td class="full" align="center">Clang 3.6</td>
 913     </tr>
 914     <tr>
 915       <td>Attributes for namespaces and enumerators</td>
 916       <td><a href="https://wg21.link/n4266">N4266</a></td>
 917       <td class="full" align="center">Clang 3.6</td>
 918     </tr>
 919     <tr>
 920       <td>Allow constant evaluation for all non-type template arguments</td>
 921       <td><a href="https://wg21.link/n4268">N4268</a></td>
 922       <td class="full" align="center">Clang 3.6</td>
 923     </tr>
 924     <!-- Kona papers -->
 925     <tr>
 926       <td>Remove deprecated <tt>register</tt> storage class</td>
 927       <td><a href="https://wg21.link/p0001r1">P0001R1</a></td>
 928       <td class="full" align="center">Clang 3.8</td>
 929     </tr>
 930     <tr>
 931       <td>Remove deprecated <tt>bool</tt> increment</td>
 932       <td><a href="https://wg21.link/p0002r1">P0002R1</a></td>
 933       <td class="full" align="center">Clang 3.8</td>
 934     </tr>
 935     <tr>
 936       <td>Make exception specifications part of the type system</td>
 937       <td><a href="https://wg21.link/p0012r1">P0012R1</a></td>
 938       <td class="full" align="center">Clang 4</td>
 939     </tr>
 940     <tr>
 941       <td><tt>__has_include</tt> in preprocessor conditionals</td>
 942       <td><a href="https://wg21.link/p0061r1">P0061R1</a></td>
 943       <td class="full" align="center">Yes</td>
 944     </tr>
 945     <!-- Jacksonville papers -->
 946     <tr>
 947       <td><tt>[[fallthrough]]</tt> attribute</td>
 948       <td><a href="https://wg21.link/p0188r1">P0188R1</a></td>
 949       <td class="full" align="center">Clang 3.9</td>
 950     </tr>
 951     <tr>
 952       <td rowspan="2"><tt>[[nodiscard]]</tt> attribute</td>
 953       <td><a href="https://wg21.link/p0189r1">P0189R1</a></td>
 954       <td class="full" align="center">Clang 3.9</td>
 955     </tr>
 956       <tr> <!-- from Cologne 2019 -->
 957         <td><a href="https://wg21.link/p1771r1">P1771R1</a> (<a href="#dr">DR</a>)</td>
 958         <td class="full" align="center">Clang 9</td>
 959       </tr>
 960     <tr>
 961       <td><tt>[[maybe_unused]]</tt> attribute</td>
 962       <td><a href="https://wg21.link/p0212r1">P0212R1</a></td>
 963       <td class="full" align="center">Clang 3.9</td>
 964     </tr>
 965     <tr>
 966       <td>Aggregate initialization of classes with base classes</td>
 967       <td><a href="https://wg21.link/p0017r1">P0017R1</a></td>
 968       <td class="full" align="center">Clang 3.9</td>
 969     </tr>
 970     <tr>
 971       <td><tt>constexpr</tt> lambda expressions</td>
 972       <td><a href="https://wg21.link/p0170r1">P0170R1</a></td>
 973       <td class="full" align="center">Clang 5</td>
 974     </tr>
 975     <tr>
 976       <td>Differing <tt>begin</tt> and <tt>end</tt> types in range-based <tt>for</tt></td>
 977       <td><a href="https://wg21.link/p0184r0">P0184R0</a></td>
 978       <td class="full" align="center">Clang 3.9</td>
 979     </tr>
 980     <tr>
 981       <td>Lambda capture of <tt>*this</tt></td>
 982       <td><a href="https://wg21.link/p0018r3">P0018R3</a></td>
 983       <td class="full" align="center">Clang 3.9</td>
 984     </tr>
 985     <tr>
 986       <td>Direct-list-initialization of <tt>enum</tt>s</td>
 987       <td><a href="https://wg21.link/p0138r2">P0138R2</a></td>
 988       <td class="full" align="center">Clang 3.9</td>
 989     </tr>
 990     <tr>
 991       <td>Hexadecimal floating-point literals</td>
 992       <td><a href="https://wg21.link/p0245r1">P0245R1</a></td>
 993       <td class="full" align="center">Yes</td>
 994     </tr>
 995     <!-- Oulu papers -->
 996     <tr>
 997       <td>Using attribute namespaces without repetition</td>
 998       <td><a href="https://wg21.link/p0028r4">P0028R4</a></td>
 999       <td class="full" align="center">Clang 3.9</td>
1000     </tr>
1001     <tr>
1002       <td>Dynamic memory allocation for over-aligned data</td>
1003       <td><a href="https://wg21.link/p0035r4">P0035R4</a></td>
1004       <td class="full" align="center">Clang 4</td>
1005     </tr>
1006     <tr>
1007       <td rowspan="4">Template argument deduction for class templates</td>
1008       <td><a href="https://wg21.link/p0091r3">P0091R3</a></td>
1009       <td rowspan="2" class="full" align="center">Clang 5</td>
1010     </tr>
1011       <tr> <!-- from Issaquah -->
1012         <td><a href="https://wg21.link/p0512r0">P0512R0</a></td>
1013       </tr>
1014       <tr>
1015         <!-- from Kona 2017 -->
1016         <td><a href="https://wg21.link/p0620r1">P0620R0</a> (<a href="#dr">DR</a>)</td>
1017         <td class="full" align="center">Clang 7</td>
1018       </tr>
1019       <tr>
1020         <!-- from Toronto 2017 -->
1021         <td><a href="https://wg21.link/p0702r1">P0702R1</a> (<a href="#dr">DR</a>)</td>
1022         <td class="full" align="center">Clang 6</td>
1023       </tr>
1024     <tr>
1025       <td>Non-type template parameters with <tt>auto</tt> type</td>
1026       <td><a href="https://wg21.link/p0127r2">P0127R2</a></td>
1027       <td class="full" align="center">Clang 4</td>
1028     </tr>
1029     <tr>
1030       <td>Guaranteed copy elision</td>
1031       <td><a href="https://wg21.link/p0135r1">P0135R1</a></td>
1032       <td class="full" align="center">Clang 4</td>
1033     </tr>
1034     <tr>
1035       <td rowspan=2>Stricter expression evaluation order</td>
1036       <td><a href="https://wg21.link/p0145r3">P0145R3</a></td>
1037       <td class="full" align="center" rowspan=2>Clang 4 <a href="#p0145">(9)</a></td>
1038     </tr>
1039     <tr>
1040       <td><a href="https://wg21.link/p0400r0">P0400R0</a></td>
1041     </tr>
1042     <tr>
1043       <td>Requirement to ignore unknown attributes</td>
1044       <td><a href="https://wg21.link/p0283r2">P0283R2</a></td>
1045       <td class="full" align="center">Yes</td>
1046     </tr>
1047     <tr>
1048       <td><tt>constexpr</tt> <em>if-statement</em>s</td>
1049       <td><a href="https://wg21.link/p0292r2">P0292R2</a></td>
1050       <td class="full" align="center">Clang 3.9</td>
1051     </tr>
1052     <tr>
1053       <td>Inline variables</td>
1054       <td><a href="https://wg21.link/p0386r2">P0386R2</a></td>
1055       <td class="full" align="center">Clang 3.9</td>
1056     </tr>
1057     <tr>
1058       <td rowspan="3">Structured bindings</td>
1059       <td><a href="https://wg21.link/p0217r3">P0217R3</a></td>
1060       <td class="full" align="center">Clang 4</td>
1061     </tr>
1062       <tr>
1063         <!-- from Jacksonville 2018 -->
1064         <td><a href="https://wg21.link/p0961r1">P0961R1</a> (<a href="#dr">DR</a>)</td>
1065         <td class="full" align="center">Clang 8</td>
1066       </tr>
1067       <tr>
1068         <!-- from Jacksonville 2018 -->
1069         <td><a href="https://wg21.link/p0969r0">P0969R0</a> (<a href="#dr">DR</a>)</td>
1070         <td class="full" align="center">Clang 8</td>
1071       </tr>
1072     <tr>
1073       <td>Separate variable and condition for <tt>if</tt> and <tt>switch</tt></td>
1074       <td><a href="https://wg21.link/p0305r1">P0305R1</a></td>
1075       <td class="full" align="center">Clang 3.9</td>
1076     </tr>
1077     <!-- Issaquah 2016 papers -->
1078     <tr>
1079       <td>Matching template template parameters to compatible arguments</td>
1080       <td><a href="https://wg21.link/p0522r0">P0522R0</a></td>
1081       <td class="partial" align="center">Partial <a href="#p0522">(10)</a></td>
1082     </tr>
1083     <tr>
1084       <td>Removing deprecated dynamic exception specifications</td>
1085       <td><a href="https://wg21.link/p0003r5">P0003R5</a></td>
1086       <td class="full" align="center">Clang 4</td>
1087     </tr>
1088     <tr>
1089       <td>Pack expansions in <em>using-declarations</em></td>
1090       <td><a href="https://wg21.link/p0195r2">P0195R2</a></td>
1091       <td class="full" align="center">Clang 4</td>
1092     </tr>
1093 </table>
1094
1095 <p>
1096 <span id="n3922">(8): This is a backwards-incompatible change that is applied to
1097 all language versions that allow type deduction from <tt>auto</tt>
1098 (per the request of the C++ committee).
1099 In Clang 3.7, a warning is emitted for all cases that would change meaning.
1100 </span><br>
1101 <span id="p0145">(9): Under the MS ABI, function parameters are destroyed from
1102 left to right in the callee. As a result, function parameters in calls to
1103 <tt>operator&lt;&lt;</tt>, <tt>operator&gt;&gt;</tt>, <tt>operator-&gt;*</tt>,
1104 <tt>operator&amp;&amp;</tt>, <tt>operator||</tt>, and <tt>operator,</tt>
1105 functions using expression syntax are no longer guaranteed to be destroyed in
1106 reverse construction order in that ABI.
1107 This is not fully supported during constant expression evaluation until Clang 12.
1108 </span><br>
1109 <span id="p0522">(10): Despite being the resolution to a Defect Report, this
1110 feature is disabled by default in all language versions, and can be enabled
1111 explicitly with the flag <tt>-frelaxed-template-template-args</tt> in Clang 4
1112 onwards.
1113 The change to the standard lacks a corresponding change for template partial
1114 ordering, resulting in ambiguity errors for reasonable and previously-valid
1115 code. This issue is expected to be rectified soon.
1116 </span>
1117 </p>
1118 </details>
1119
1120 <h2 id="cxx14">C++14 implementation status</h2>
1121
1122 <p>Clang 3.4 and later implement all of the <a
1123     href="https://www.iso.org/standard/64029.html">ISO
1124     C++ 2014 standard</a>.</p>
1125
1126 <p>You can use Clang in C++14 mode with the <code>-std=c++14</code> option
1127 (use <code>-std=c++1y</code> in Clang 3.4 and earlier).</p>
1128
1129 <details>
1130 <summary>List of features and minimum Clang version with support</summary>
1131
1132 <table width="689" border="1" cellspacing="0">
1133  <tr>
1134     <th>Language Feature</th>
1135     <th>C++14 Proposal</th>
1136     <th>Available in Clang?</th>
1137  </tr>
1138     <tr>
1139       <td>Tweak to certain C++ contextual conversions</td>
1140       <td><a href="https://wg21.link/n3323">N3323</a></td>
1141       <td class="full" align="center">Clang 3.4</td>
1142     </tr>
1143     <tr>
1144       <td>Binary literals</td>
1145       <td><a href="https://wg21.link/n3472">N3472</a></td>
1146       <td class="full" align="center">Clang 2.9</td>
1147     </tr>
1148     <tr>
1149       <td>decltype(auto)</td>
1150       <td rowspan=2 style="vertical-align:middle"><a href="https://wg21.link/n3638">N3638</a></td>
1151       <td class="full" align="center">Clang 3.3</td>
1152     </tr>
1153     <tr>
1154       <td>Return type deduction for normal functions</td>
1155       <td class="full" align="center">Clang 3.4</td>
1156     </tr>
1157     <tr>
1158       <td>Initialized lambda captures</td>
1159       <td><a href="https://wg21.link/n3648">N3648</a></td>
1160       <td class="full" align="center">Clang 3.4</td>
1161     </tr>
1162     <tr>
1163       <td>Generic lambdas</td>
1164       <td><a href="https://wg21.link/n3649">N3649</a></td>
1165       <td class="full" align="center">Clang 3.4</td>
1166     </tr>
1167     <tr>
1168       <td>Variable templates</td>
1169       <td><a href="https://wg21.link/n3651">N3651</a></td>
1170       <td class="full" align="center">Clang 3.4</td>
1171     </tr>
1172     <tr>
1173       <td>Relaxing requirements on constexpr functions</td>
1174       <td><a href="https://wg21.link/n3652">N3652</a></td>
1175       <td class="full" align="center">Clang 3.4</td>
1176     </tr>
1177     <tr>
1178       <td>Member initializers and aggregates</td>
1179       <td><a href="https://wg21.link/n3653">N3653</a></td>
1180       <td class="full" align="center">Clang 3.3</td>
1181     </tr>
1182     <tr>
1183       <td>Clarifying memory allocation</td>
1184       <td><a href="https://wg21.link/n3664">N3664</a></td>
1185       <td class="full" align="center">Clang 3.4</td>
1186     </tr>
1187     <tr>
1188       <td><tt>[[deprecated]]</tt> attribute</td>
1189       <td><a href="https://wg21.link/n3760">N3760</a></td>
1190       <td class="full" align="center">Clang 3.4</td>
1191     </tr>
1192     <tr>
1193       <td>Single quotation mark as digit separator</td>
1194       <td><a href="https://wg21.link/n3781">N3781</a></td>
1195       <td class="full" align="center">Clang 3.4</td>
1196     </tr>
1197     <tr>
1198       <td>C++ Sized Deallocation</td>
1199       <td><a href="https://wg21.link/n3778">N3778</a></td>
1200       <td class="full" align="center">Clang 3.4 <a href="#n3778">(7)</a></td>
1201     </tr>
1202 </table>
1203
1204 <p>
1205 <span id="n3778">(7): In Clang 3.7 and later, sized deallocation is only enabled
1206 if the user passes the <code>-fsized-deallocation</code> flag. The user must
1207 supply definitions of the sized deallocation functions, either by providing them
1208 explicitly or by using a C++ standard library that does. <code>libstdc++</code>
1209 added these functions in version 5.0, and <code>libc++</code> added them in
1210 version 3.7.
1211 </span>
1212 </p>
1213 </details>
1214
1215 <h2 id="cxx11">C++11 implementation status</h2>
1216
1217 <p>Clang 3.3 and later implement all of the <a
1218   href="https://www.iso.org/standard/50372.html">ISO
1219   C++ 2011 standard</a>.</p>
1220
1221 <p>You can use Clang in C++11 mode with the <code>-std=c++11</code>
1222 option. Clang's C++11 mode can be used with
1223 <a href="https://libcxx.llvm.org/">libc++</a> or with gcc's libstdc++.</p>
1224
1225 <details>
1226 <summary>List of features and minimum Clang version with support</summary>
1227
1228 <table width="689" border="1" cellspacing="0">
1229  <tr>
1230     <th>Language Feature</th>
1231     <th>C++11 Proposal</th>
1232     <th>Available in Clang?</th>
1233  </tr>
1234      <tr>
1235       <td rowspan="2">Rvalue references</td>
1236       <td><a href="https://wg21.link/n2118">N2118</a></td>
1237       <td class="full" align="center">Clang 2.9</td>
1238       <tr> <!-- from Kona 2019-->
1239         <td><a href="https://wg21.link/p1825r0">P1825R0</a> (<a href="#dr">DR</a>)</td>
1240         <td class="full" align="center">Clang 13</td>
1241       </tr>
1242     </tr>
1243     <tr>
1244       <td>&nbsp;&nbsp;&nbsp;&nbsp;Rvalue references for <code>*this</code></td>
1245       <td><a href="https://wg21.link/n2439">N2439</a></td>
1246       <td class="full" align="center">Clang 2.9</td>
1247     </tr>
1248     <tr>
1249       <td>Initialization of class objects by rvalues</td>
1250       <td><a href="https://wg21.link/n1610">N1610</a></td>
1251       <td class="full" align="center">Clang 2.9</td>
1252     </tr>
1253     <tr>
1254       <td>Non-static data member initializers</td>
1255       <td><a href="https://wg21.link/n2756">N2756</a></td>
1256       <td class="full" align="center">Clang 3.0</td>
1257     </tr>
1258     <tr>
1259       <td>Variadic templates</td>
1260       <td><a href="https://wg21.link/n2242">N2242</a></td>
1261       <td class="full" align="center">Clang 2.9</td>
1262     </tr>
1263     <tr>
1264       <td>&nbsp;&nbsp;&nbsp;&nbsp;Extending variadic template template parameters</td>
1265       <td><a href="https://wg21.link/n2555">N2555</a></td>
1266       <td class="full" align="center">Clang 2.9</td>
1267     </tr>
1268     <tr>
1269       <td rowspan="3">Initializer lists</td>
1270       <td><a href="https://wg21.link/n2672">N2672</a></td>
1271       <td class="full" align="center">Clang 3.1</td>
1272     </tr>
1273       <tr> <!-- from Kona 2019-->
1274         <td><a href="https://wg21.link/p1009r2">P1009R2</a> (<a href="#dr">DR</a>)</td>
1275         <td class="full" align="center">Clang 9</td>
1276       </tr>
1277       <tr> <!-- from Prague-->
1278         <td><a href="https://wg21.link/p1957r2">P1957R2</a> (<a href="#dr">DR</a>)</td>
1279         <td class="full" align="center">Clang 11</td>
1280       </tr>
1281     <tr>
1282       <td>Static assertions</td>
1283       <td><a href="https://wg21.link/n1720">N1720</a></td>
1284       <td class="full" align="center">Clang 2.9</td>
1285     </tr>
1286     <tr>
1287       <td><code>auto</code>-typed variables</td>
1288       <td><a href="https://wg21.link/n1984">N1984</a></td>
1289       <td class="full" align="center">Clang 2.9</td>
1290     </tr>
1291     <tr>
1292       <td>&nbsp;&nbsp;&nbsp;&nbsp;Multi-declarator <code>auto</code></td>
1293       <td><a href="https://wg21.link/n1737">N1737</a></td>
1294       <td class="full" align="center">Clang 2.9</td>
1295     </tr>
1296     <tr>
1297       <td>&nbsp;&nbsp;&nbsp;&nbsp;Removal of auto as a storage-class specifier</td>
1298       <td><a href="https://wg21.link/n2546">N2546</a></td>
1299       <td class="full" align="center">Clang 2.9</td>
1300     </tr>
1301     <tr>
1302       <td>&nbsp;&nbsp;&nbsp;&nbsp;New function declarator syntax</td>
1303       <td><a href="https://wg21.link/n2541">N2541</a></td>
1304       <td class="full" align="center">Clang 2.9</td>
1305     </tr>
1306     <tr>
1307       <td rowspan="2">Lambda expressions</td>
1308       <td><a href="https://wg21.link/n2927">N2927</a></td>
1309       <td class="full" align="center">Clang 3.1</td>
1310     </tr>
1311       <tr>
1312         <!-- from Albuquerque 2017 -->
1313         <td><a href="https://wg21.link/p0588r1">P0588R1</a> (<a href="#dr">DR</a>)</td>
1314         <td class="none" align="center">No</td>
1315       </tr>
1316     <tr>
1317       <td>Declared type of an expression</td>
1318       <td><a href="https://wg21.link/n2343">N2343</a></td>
1319       <td class="full" align="center">Clang 2.9</td>
1320     </tr>
1321     <tr>
1322       <td>&nbsp;&nbsp;&nbsp;&nbsp;Incomplete return types</td>
1323       <td><a href="https://wg21.link/n3276">N3276</a></td>
1324       <td class="full" align="center">Clang 3.1</td>
1325     </tr>
1326     <tr>
1327       <td>Right angle brackets</td>
1328       <td><a href="https://wg21.link/n1757">N1757</a></td>
1329       <td class="full" align="center">Clang 2.9</td>
1330     </tr>
1331     <tr>
1332       <td>Default template arguments for function templates</td>
1333       <td><a href="https://wg21.link/cwg226">DR226</a></td>
1334       <td class="full" align="center">Clang 2.9</td>
1335     </tr>
1336     <tr>
1337       <td>Solving the SFINAE problem for expressions</td>
1338       <td><a href="https://wg21.link/n2634">DR339</a></td>
1339       <td class="full" align="center">Clang 2.9</td>
1340     </tr>
1341     <tr>
1342       <td>Alias templates</td>
1343       <td><a href="https://wg21.link/n2258">N2258</a></td>
1344       <td class="full" align="center">Clang 3.0</td>
1345     </tr>
1346     <tr>
1347       <td>Extern templates</td>
1348       <td><a href="https://wg21.link/n1987">N1987</a></td>
1349       <td class="full" align="center">Clang 2.9</td>
1350     </tr>
1351     <tr>
1352       <td>Null pointer constant</td>
1353       <td><a href="https://wg21.link/n2431">N2431</a></td>
1354       <td class="full" align="center">Clang 3.0</td>
1355     </tr>
1356     <tr>
1357       <td>Strongly-typed enums</td>
1358       <td><a href="https://wg21.link/n2347">N2347</a></td>
1359       <td class="full" align="center">Clang 2.9</td>
1360     </tr>
1361     <tr>
1362       <td>Forward declarations for enums</td>
1363       <td><a href="https://wg21.link/n2764">N2764</a>
1364       <br><a href="https://wg21.link/cwg1206">DR1206</a></td>
1365       <td class="full" align="center">Clang 3.1</td>
1366     </tr>
1367     <tr>
1368       <td>Standardized attribute syntax</td>
1369       <td><a href="https://wg21.link/n2761">N2761</a></td>
1370       <td class="full" align="center">Clang 3.3 <a href="#n2761">(1)</a></td>
1371     </tr>
1372     <tr>
1373       <td rowspan="2">Generalized constant expressions</td>
1374       <td><a href="https://wg21.link/n2235">N2235</a></td>
1375       <td class="full" align="center">Clang 3.1</td>
1376     </tr>
1377       <tr>
1378         <!-- from Albuquerque 2017 -->
1379         <td><a href="https://wg21.link/p0859r0">P0859R0</a> (<a href="#dr">DR</a>)</td>
1380         <td class="full" align="center">Clang 8</td>
1381       </tr>
1382     <tr>
1383       <td>Alignment support</td>
1384       <td><a href="https://wg21.link/n2341">N2341</a></td>
1385       <td class="full" align="center">Clang 3.3</td>
1386     </tr>
1387     <tr>
1388       <td>Conditionally-support behavior</td>
1389       <td><a href="https://wg21.link/n1627">N1627</a></td>
1390       <td class="full" align="center">Clang 2.9</td>
1391     </tr>
1392     <tr>
1393       <td>Changing undefined behavior into diagnosable errors</td>
1394       <td><a href="https://wg21.link/n1727">N1727</a></td>
1395       <td class="full" align="center">Clang 2.9</td>
1396     </tr>
1397     <tr>
1398       <td>Delegating constructors</td>
1399       <td><a href="https://wg21.link/n1986">N1986</a></td>
1400       <td class="full" align="center">Clang 3.0</td>
1401     </tr>
1402     <tr>
1403       <td rowspan="2">Inheriting constructors</td>
1404       <td><a href="https://wg21.link/n2540">N2540</a></td>
1405       <td class="full" align="center">Clang 3.3</td>
1406     </tr>
1407       <tr>
1408         <!-- from Kona 2015 -->
1409         <td><a href="https://wg21.link/p0136r1">P0136R1</a> (<a href="#dr">DR</a>)</td>
1410         <td class="full" align="center">Clang 3.9</td>
1411       </tr>
1412     <tr>
1413       <td>Explicit conversion operators</td>
1414       <td><a href="https://wg21.link/n2437">N2437</a></td>
1415       <td class="full" align="center">Clang 3.0</td>
1416     </tr>
1417     <tr>
1418       <td>New character types</td>
1419       <td><a href="https://wg21.link/n2249">N2249</a></td>
1420       <td class="full" align="center">Clang 2.9</td>
1421     </tr>
1422     <tr>
1423       <td>Unicode string literals</td>
1424       <td><a href="https://wg21.link/n2442">N2442</a></td>
1425       <td class="full" align="center">Clang 3.0</td>
1426     </tr>
1427     <tr>
1428       <td>Raw string literals</td>
1429       <td><a href="https://wg21.link/n2442">N2442</a></td>
1430       <td class="full" align="center">Clang 3.0</td>
1431     </tr>
1432     <tr>
1433       <td>Universal character names in literals</td>
1434       <td><a href="https://wg21.link/n2170">N2170</a></td>
1435       <td class="full" align="center">Clang 3.1</td>
1436     </tr>
1437     <tr>
1438       <td>User-defined literals</td>
1439       <td><a href="https://wg21.link/n2765">N2765</a></td>
1440       <td class="full" align="center">Clang 3.1</td>
1441     </tr>
1442     <tr>
1443       <td>Standard Layout Types</td>
1444       <td><a href="https://wg21.link/n2342">N2342</a></td>
1445       <td class="full" align="center">Clang 3.0</td>
1446     </tr>
1447     <tr>
1448       <td rowspan="2">Defaulted functions</td>
1449       <td><a href="https://wg21.link/n2346">N2346</a></td>
1450       <td class="full" align="center">Clang 3.0</td>
1451     </tr>
1452       <tr> <!-- from Kona 2019-->
1453         <td><a href="https://wg21.link/p1286r2">P1286R2</a> (<a href="#dr">DR</a>)</td>
1454         <td class="full" align="center">Clang 9</td>
1455       </tr>
1456     <tr>
1457       <td>Deleted functions</td>
1458       <td><a href="https://wg21.link/n2346">N2346</a></td>
1459       <td class="full" align="center">Clang 2.9</td>
1460     </tr>
1461     <tr>
1462       <td>Extended friend declarations</td>
1463       <td><a href="https://wg21.link/n1791">N1791</a></td>
1464       <td class="full" align="center">Clang 2.9</td>
1465     </tr>
1466     <tr>
1467       <td>Extending <code>sizeof</code></td>
1468       <td><a href="https://wg21.link/n2253">N2253</a>
1469       <br><a href="https://wg21.link/cwg850">DR850</a></td>
1470       <td class="full" align="center">Clang 3.1</td>
1471     </tr>
1472     <tr>
1473       <td>Inline namespaces</td>
1474       <td><a href="https://wg21.link/n2535">N2535</a></td>
1475       <td class="full" align="center">Clang 2.9</td>
1476     </tr>
1477     <tr>
1478       <td>Unrestricted unions</td>
1479       <td><a href="https://wg21.link/n2544">N2544</a></td>
1480       <td class="full" align="center">Clang 3.1</td>
1481     </tr>
1482     <tr>
1483       <td>Local and unnamed types as template arguments</td>
1484       <td><a href="https://wg21.link/n2657">N2657</a></td>
1485       <td class="full" align="center">Clang 2.9</td>
1486     </tr>
1487     <tr>
1488       <td rowspan="2">Range-based for</td>
1489       <td><a href="https://wg21.link/n2930">N2930</a></td>
1490       <td class="full" align="center">Clang 3.0</td>
1491     </tr>
1492       <tr>
1493         <!-- from Jacksonville 2018 -->
1494         <td><a href="https://wg21.link/p0962r1">P0962R1</a> (<a href="#dr">DR</a>)</td>
1495         <td class="full" align="center">Clang 8</td>
1496       </tr>
1497     <tr>
1498       <td>Explicit virtual overrides</td>
1499       <td><a href="https://wg21.link/n2928">N2928</a>
1500       <br><a href="https://wg21.link/n3206">N3206</a>
1501       <br><a href="https://wg21.link/n3272">N3272</a></td>
1502       <td class="full" align="center">Clang 3.0</td>
1503     </tr>
1504     <tr>
1505       <td>Minimal support for garbage collection and reachability-based leak detection</td>
1506       <td><a href="https://wg21.link/n2670">N2670</a></td>
1507       <td class="na" align="center">N/A <a href="#n2670">(2)</a></td>
1508     </tr>
1509     <tr>
1510       <td>Allowing move constructors to throw [noexcept]</td>
1511       <td><a href="https://wg21.link/n3050">N3050</a></td>
1512       <td class="full" align="center">Clang 3.0</td>
1513     </tr>
1514     <tr>
1515       <td>Defining move special member functions</td>
1516       <td><a href="https://wg21.link/n3053">N3053</a></td>
1517       <td class="full" align="center">Clang 3.0</td>
1518     </tr>
1519
1520     <tr class="separator">
1521       <th align="center" colspan="3">Concurrency</th>
1522     </tr>
1523     <tr>
1524       <td>Sequence points</td>
1525       <td><a href="https://wg21.link/n2239">N2239</a></td>
1526       <td class="full" align="center">Clang 3.3</td>
1527     </tr>
1528     <tr>
1529       <td>Atomic operations</td>
1530       <td><a href="https://wg21.link/n2427">N2427</a></td>
1531       <td class="full" align="center">Clang 3.1</td>
1532     </tr>
1533     <tr>
1534       <td>Strong Compare and Exchange</td>
1535       <td><a href="https://wg21.link/n2748">N2748</a></td>
1536       <td class="full" align="center">Clang 3.1 <a href="#n2748">(3)</a></td>
1537     </tr>
1538     <tr>
1539       <td>Bidirectional Fences</td>
1540       <td><a href="https://wg21.link/n2752">N2752</a></td>
1541       <td class="full" align="center">Clang 3.1</td>
1542     </tr>
1543
1544     <tr>
1545       <td>Memory model</td>
1546       <td><a href="https://wg21.link/n2429">N2429</a></td>
1547       <td class="full" align="center">Clang 3.2</td>
1548     </tr>
1549     <tr>
1550       <td>Data-dependency ordering: atomics and memory model</td>
1551       <td><a href="https://wg21.link/n2664">N2664</a></td>
1552       <td class="full" align="center">Clang 3.2 <a href="#n2664">(4)</a></td>
1553     </tr>
1554     <tr>
1555       <td>Propagating exceptions</td>
1556       <td><a href="https://wg21.link/n2179">N2179</a></td>
1557       <td class="full" align="center">Clang 2.9</td>
1558     </tr>
1559     <tr>
1560       <td>Allow atomics use in signal handlers</td>
1561       <td><a href="https://wg21.link/n2547">N2547</a></td>
1562       <td class="full" align="center">Clang 3.1</td>
1563     </tr>
1564     <tr>
1565       <td>Thread-local storage</td>
1566       <td><a href="https://wg21.link/n2659">N2659</a></td>
1567       <td class="full" align="center">Clang 3.3 <a href="#n2659">(5)</a></td>
1568     </tr>
1569     <tr>
1570       <td>Dynamic initialization and destruction with concurrency</td>
1571       <td><a href="https://wg21.link/n2660">N2660</a></td>
1572       <td class="full" align="center">Clang 2.9</td>
1573     </tr>
1574
1575     <tr class="separator">
1576       <th align="center" colspan="3">C99 Features in C++11</th>
1577     </tr>
1578     <tr>
1579       <td><code>__func__</code> predefined identifier</td>
1580       <td><a href="https://wg21.link/n2340">N2340</a></td>
1581       <td class="full" align="center">Clang 2.9</td>
1582     </tr>
1583     <tr>
1584       <td>C99 preprocessor</td>
1585       <td><a href="https://wg21.link/n1653">N1653</a></td>
1586       <td class="full" align="center">Clang 2.9</td>
1587     </tr>
1588     <tr>
1589       <td><code>long long</code></td>
1590       <td><a href="https://wg21.link/n1811">N1811</a></td>
1591       <td class="full" align="center">Clang 2.9</td>
1592     </tr>
1593     <tr>
1594       <td>Extended integral types</td>
1595       <td><a href="https://wg21.link/n1988">N1988</a></td>
1596       <td class="na" align="center">N/A <a href="#n1988">(6)</a></td>
1597     </tr>
1598 </table>
1599
1600 <p>
1601 <span id="n2761">(1): The <code>[[carries_dependency]]</code> attribute
1602 has no effect.</span><br>
1603 <span id="n2670">(2): No compiler changes are required for an implementation
1604 such as Clang that does not provide garbage collection.</span><br>
1605 <span id="n2748">(3): All compare-exchange operations are emitted as
1606 strong compare-exchanges.</span><br>
1607 <span id="n2664">(4): <code>memory_order_consume</code> is lowered to
1608 <code>memory_order_acquire</code>.</span><br>
1609 <span id="n2659">(5): <code>thread_local</code> support
1610 requires a C++ runtime library providing <code>__cxa_thread_atexit</code>, such
1611 as <a href="https://libcxxabi.llvm.org">libc++abi</a> 3.6 or later,
1612 or libsupc++ 4.8 or later.</span><br>
1613 <span id="n1988">(6): No compiler changes are required for an implementation
1614 such as Clang that does not provide any extended integer types.
1615 <code>__int128</code> is not treated as an extended integer type,
1616 because changing <code>intmax_t</code> would be an ABI-incompatible
1617 change.</span>
1618 </p>
1619 </details>
1620
1621
1622 <h2 id="cxx98">C++98 implementation status</h2>
1623
1624 <p>Clang implements all of the ISO C++ 1998 standard
1625   (including the defects addressed in the ISO C++ 2003 standard)
1626   except for <tt>export</tt> (which was removed in C++11).
1627
1628 <h2 id="dr">Defect reports</h2>
1629
1630 <p>Clang generally aims to implement resolutions to Defect Reports (bug fixes
1631 against prior standards) retroactively, in all prior standard versions where
1632 the fix is meaningful. Significant Defect Report changes to language features
1633 after the publication of the relevant standard are marked (DR) in the above
1634 table.</p>
1635
1636 <p>Clang also has a test suite for conformance to resolutions for issues on the
1637 <a href="http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_toc.html">C++ core issues list</a>,
1638 most of which are considered Defect Reports.
1639 <a href="cxx_dr_status.html">Implementation status for C++ core issues</a> based on
1640 that test suite is tracked on a separate page.</p>
1641
1642 <h2 id="ts">Technical specifications and standing documents</h2>
1643
1644 <p>ISO C++ also publishes a number of documents describing additional language
1645 and library features that are not part of standard C++.</p>
1646
1647 <details open>
1648 <summary>List of features and minimum Clang version with support</summary>
1649
1650 <table width="689" border="1" cellspacing="0">
1651  <tr>
1652     <th>Document</th>
1653     <th>Latest draft</th>
1654     <th>Compiler flag</th>
1655     <th>Available in Clang?</th>
1656  </tr>
1657     <tr id="sd6">
1658       <td rowspan="7">SD-6: SG10 feature test recommendations</td>
1659       <td rowspan="7"><a href="https://isocpp.org/std/standing-documents/sd-6-sg10-feature-test-recommendations">SD-6</a></td>
1660       <td rowspan="7">N/A</td>
1661       <td class="full" align="center">
1662         Clang 3.4 (<a href="https://wg21.link/n3745">N3745</a>)</br>
1663       </td>
1664     </tr>
1665     <tr>
1666       <td class="full" align="center">
1667         Clang 3.6 (<a href="https://wg21.link/n4200">N4200</a>)</a>
1668       </td>
1669     </tr>
1670     <tr>
1671       <td class="full" align="center">
1672         Clang 4 (<a href="https://wg21.link/p0096r3">P0096R3</a>)</a>
1673       </td>
1674     </tr>
1675     <tr>
1676       <td class="full" align="center">
1677         Clang 5 (<a href="https://wg21.link/p0096r4">P0096R4</a>)</a>
1678       </td>
1679     </tr>
1680     <tr>
1681       <td class="full" align="center">
1682         Clang 7 (<a href="https://wg21.link/p0096r5">P0096R5</a>)</a>
1683       </td>
1684     </tr>
1685     <tr>
1686       <td class="full" align="center">
1687         Clang 9 (<a href="https://wg21.link/p1353r0">P1353R0</a>)
1688       </td>
1689     </tr>
1690     <tr>
1691       <td class="full" align="center">
1692         Clang 10 (<a href="https://wg21.link/p1902r1">P1902R1</a>)</a>
1693       </td>
1694     </tr>
1695     <!-- No compiler support is known to be needed for:
1696            * Concurrency TS
1697            * Parallelism TS (v1, v2)
1698            * Ranges TS
1699            * Networking TS
1700            * File System TS
1701     -->
1702     <tr>
1703       <td>[TS] Concepts</td>
1704       <td><a href="https://wg21.link/p0121r0">P0121R0</a></td>
1705       <td></td>
1706       <td class="na" align="center">Superseded by <a href="#p0734">P0734R0</a></td>
1707     </tr>
1708     <tr>
1709       <!-- track unimplemented Coroutines features: p0913r1 p0914r1 p1356r0 -->
1710       <td rowspan="2">[TS] Coroutines</td>
1711       <td rowspan="2"><a href="https://isocpp.org/files/papers/N4663.pdf">N4663</a></td>
1712       <td><tt>-fcoroutines-ts<br>-stdlib=libc++</tt></td>
1713       <td class="full" align="center">Clang 5</td>
1714     </tr>
1715     <tr>
1716       <td><tt>-std=c++20<br>-stdlib=libc++</tt></td>
1717       <td class="na" align="center">Superseded by <a href="#p0912">P0912R5</a></td>
1718     </tr>
1719     <tr>
1720       <td>[TS] Library Fundamentals, Version 1 (invocation type traits)</td>
1721       <td><a href="https://wg21.link/n4480">N4480</a></td>
1722       <td>N/A</td>
1723       <td class="none" align="center">No</td>
1724     </tr>
1725     <tr>
1726       <td>[TS] Library Fundamentals, Version 2 (<tt>source_location</tt>)</td>
1727      <td><a href="https://wg21.link/n4617">N4617</a></td>
1728       <td>N/A</td>
1729       <td class="full" align="center">Clang 9 (<a href="docs/LanguageExtensions.html#source-location-builtins">documentation</a>)</td>
1730     </tr>
1731     <tr>
1732       <td>[TS] Modules</td>
1733       <td><a href="https://wg21.link/n4720">N4720</a></td>
1734       <td><tt>-fmodules-ts</tt></td>
1735       <td class="na" align="center">Superseded by <a href="#p1103">P1103R3</a></td>
1736     </tr>
1737     <tr>
1738       <td>[DRAFT TS] Reflection</td>
1739       <td><a href="https://wg21.link/n4818">N4818</a></td>
1740       <td></td>
1741       <td class="none" align="center">No</td>
1742     </tr>
1743     <tr>
1744       <td>[TS] Transactional Memory</td>
1745       <td><a href="https://wg21.link/n4514">N4514</a></td>
1746       <td></td>
1747       <td class="none" align="center">No</td>
1748     </tr>
1749 </table>
1750 </details>
1751
1752 </div>
1753 </body>
1754 </html>