libstdc++-v3/doc/xml/manual/status_cxx2017.xml

   1 <section xmlns="http://docbook.org/ns/docbook" version="5.0"
   2          xml:id="status.iso.201z" xreflabel="Status C++ 201z">
   3 <?dbhtml filename="status_iso_cxx201z.html"?>
   4
   5 <info><title>C++ 201z</title>
   6   <keywordset>
   7     <keyword>ISO C++</keyword>
   8     <keyword>201z</keyword>
   9   </keywordset>
  10 </info>
  11
  12 <para>
  13 In this implementation the <literal>-std=gnu++1z</literal> or
  14 <literal>-std=c++1z</literal> flag must be used to enable language
  15 and library
  16 features. See <link linkend="manual.intro.using.flags">dialect</link>
  17 options. The pre-defined symbol
  18 <constant>__cplusplus</constant> is used to check for the
  19 presence of the required flag.
  20 </para>
  21
  22 <para>
  23 This section describes the C++1z and library TS support in mainline GCC SVN,
  24 not in any particular release.
  25 </para>
  26
  27 <para>
  28 The following table lists new library features that have been accepted into
  29 the C++1z working draft. The "Proposal" column provides a link to the
  30 ISO C++ committee proposal that describes the feature, while the "Status"
  31 column indicates the first version of GCC that contains an implementation of
  32 this feature (if it has been implemented).
  33 The "SD-6 Feature Test" column shows the corresponding macro or header from
  34 <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="https://isocpp.org/std/standing-documents/sd-6-sg10-feature-test-recommendations">SD-6:
  35 Feature-testing recommendations for C++</link>.
  36 </para>
  37
  38 <table frame="all" xml:id="table.cxx1z_status">
  39 <title>C++ 201z Implementation Status</title>
  40
  41 <tgroup cols="4" align="left" colsep="0" rowsep="1">
  42 <colspec colname="c1"/>
  43 <colspec colname="c2"/>
  44 <colspec colname="c3"/>
  45 <colspec colname="c4"/>
  46   <thead>
  47     <row>
  48       <entry>Library Feature</entry>
  49       <entry>Proposal</entry>
  50       <entry>Status</entry>
  51       <entry>SD-6 Feature Test</entry>
  52     </row>
  53   </thead>
  54
  55   <tbody>
  56
  57     <row>
  58       <?dbhtml bgcolor="#C8B0B0" ?>
  59       <entry>
  60         <code>constexpr std::hardware_{constructive,destructive}_interference_size</code>
  61       </entry>
  62       <entry>
  63         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0154r1.html">
  64         P0154R1
  65         </link>
  66       </entry>
  67       <entry align="center"> No </entry>
  68       <entry> <code>__cpp_lib_hardware_interference_size >= 201603</code> </entry>
  69     </row>
  70
  71     <row>
  72       <entry> Core Issue 1776: Replacement of class objects containing reference members</entry>
  73       <entry>
  74         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0137r1.html">
  75         P0137R1
  76         </link>
  77       </entry>
  78       <entry align="center"> 7 </entry>
  79       <entry> <code>__cpp_lib_launder >= 201606</code> </entry>
  80     </row>
  81
  82     <row>
  83       <entry>Wording for <code>std::uncaught_exceptions</code></entry>
  84       <entry>
  85         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/JTC1/sc22/WG21/docs/papers/2014/n4259.pdf">
  86           N4259
  87         </link>
  88       </entry>
  89       <entry align="center">6.1</entry>
  90       <entry><code>__cpp_lib_uncaught_exceptions >= 201411</code></entry>
  91     </row>
  92
  93     <row>
  94       <entry> Variant: a type-safe union for C++17 </entry>
  95       <entry>
  96         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0088r3.html">
  97         P0088R3
  98         </link>
  99       </entry>
 100       <entry align="center"> 7 </entry>
 101       <entry> <code>__has_include(&lt;variant&gt;)</code> </entry>
 102     </row>
 103
 104     <row>
 105       <entry> Library Fundamentals V1 TS Components: <code>optional</code> </entry>
 106       <entry>
 107         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0220r1.html">
 108         P0220R1
 109         </link>
 110       </entry>
 111       <entry align="center"> 7 </entry>
 112       <entry> <code>__has_include(&lt;optional&gt;)</code> </entry>
 113     </row>
 114
 115     <row>
 116       <entry> Library Fundamentals V1 TS Components: <code>any</code> </entry>
 117       <entry>
 118         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0220r1.html">
 119         P0220R1
 120         </link>
 121       </entry>
 122       <entry align="center"> 7 </entry>
 123       <entry> <code>__has_include(&lt;any&gt;)</code> </entry>
 124     </row>
 125
 126     <row>
 127       <entry> Library Fundamentals V1 TS Components: <code>string_view</code> </entry>
 128       <entry>
 129         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0220r1.html">
 130         P0220R1
 131         </link>
 132       </entry>
 133       <entry align="center"> 7 </entry>
 134       <entry> <code>__has_include(&lt;string_view&gt;)</code> </entry>
 135     </row>
 136
 137     <row>
 138       <?dbhtml bgcolor="#C8B0B0" ?>
 139       <entry> Library Fundamentals V1 TS Components: <code>memory_resource</code> </entry>
 140       <entry>
 141         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0220r1.html">
 142         P0220R1
 143         </link>
 144       </entry>
 145       <entry align="center"> No </entry>
 146       <entry> <code>__has_include(&lt;memory_resource&gt;)</code> </entry>
 147     </row>
 148
 149     <row>
 150       <entry> Library Fundamentals V1 TS Components: <code>apply</code> </entry>
 151       <entry>
 152         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0220r1.html">
 153         P0220R1
 154         </link>
 155       </entry>
 156       <entry align="center"> 7 </entry>
 157       <entry> <code>__cpp_lib_apply >= 201603</code> </entry>
 158     </row>
 159
 160     <row>
 161       <entry> Library Fundamentals V1 TS Components: <code>shared_ptr&lt;T[]&gt;</code> </entry>
 162       <entry>
 163         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0220r1.html">
 164         P0220R1
 165         </link>
 166       </entry>
 167       <entry align="center"> 7 </entry>
 168       <entry> <code>__cpp_lib_shared_ptr_arrays >= 201603</code> </entry>
 169     </row>
 170
 171     <row>
 172       <entry> Library Fundamentals V1 TS Components: Searchers </entry>
 173       <entry>
 174         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0220r1.html">
 175         P0220R1
 176         </link>
 177       </entry>
 178       <entry align="center"> 7 </entry>
 179       <entry> <code>__cpp_lib_boyer_moore_searcher >= 201603</code> </entry>
 180     </row>
 181
 182     <row>
 183       <entry> Library Fundamentals V1 TS Components: Sampling </entry>
 184       <entry>
 185         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0220r1.html">
 186         P0220R1
 187         </link>
 188       </entry>
 189       <entry align="center"> 7 </entry>
 190       <entry> <code>__cpp_lib_sample >= 201603</code> </entry>
 191     </row>
 192
 193     <row>
 194       <entry> Constant View: A proposal for a <code>std::as_const</code> helper function template       </entry>
 195       <entry>
 196         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="">
 197         P0007R1
 198         </link>
 199       </entry>
 200       <entry align="center"> 7 </entry>
 201       <entry><code> __cpp_lib_as_const >= 201510 </code></entry>
 202     </row>
 203
 204     <row>
 205       <entry> Improving pair and tuple </entry>
 206       <entry>
 207         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4387">
 208         N4387
 209         </link>
 210       </entry>
 211       <entry align="center"> 6.1 </entry>
 212       <entry> N/A </entry>
 213     </row>
 214
 215     <row>
 216       <entry> <code>make_from_tuple</code>: apply for construction </entry>
 217       <entry>
 218         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0209r2.pdf">
 219         P0209R2
 220         </link>
 221       </entry>
 222       <entry align="center"> 7 </entry>
 223       <entry><code> __cpp_lib_make_from_tuple >= 201606 </code></entry>
 224     </row>
 225
 226     <row>
 227       <?dbhtml bgcolor="#C8B0B0" ?>
 228       <entry>
 229         Removing <code>auto_ptr</code>, <code>random_shuffle()</code>,
 230         And Old <code>&lt;functional&gt;</code> Stuff
 231       </entry>
 232       <entry>
 233         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4190.htm">
 234           N4190
 235         </link>
 236       </entry>
 237       <entry align="center">No (kept for backwards compatibility)</entry>
 238       <entry/>
 239     </row>
 240
 241     <row>
 242       <?dbhtml bgcolor="#C8B0B0" ?>
 243       <entry> Deprecating Vestigial Library Parts in C++17 </entry>
 244       <entry>
 245         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0174r2.html">
 246         P0174R2
 247         </link>
 248       </entry>
 249       <entry align="center"> No </entry>
 250       <entry/>
 251     </row>
 252
 253     <row>
 254       <entry> Making <code>std::owner_less</code> more flexible </entry>
 255       <entry>
 256         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/p0074r0.html">
 257         P0074R0
 258         </link>
 259       </entry>
 260       <entry align="center"> 7 </entry>
 261       <entry><code> __cpp_lib_transparent_operators >= 201510 </code></entry>
 262     </row>
 263
 264     <row>
 265       <entry> <code>std::addressof</code> should be constexpr </entry>
 266       <entry>
 267         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0304r0.html#2296">
 268         LWG2296
 269         </link>
 270       </entry>
 271       <entry align="center"> 7 </entry>
 272       <entry><code> __cpp_lib_addressof_constexpr >= 201603 </code></entry>
 273     </row>
 274
 275     <row>
 276       <entry> Safe conversions in <code>unique_ptr&lt;T[]&gt;</code> </entry>
 277       <entry>
 278         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4089.pdf">
 279         N4089
 280         </link>
 281       </entry>
 282       <entry align="center"> 6 </entry>
 283       <entry/>
 284     </row>
 285
 286     <row>
 287       <entry> LWG 2228: Missing SFINAE rule in unique_ptr templated assignment </entry>
 288       <entry>
 289         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4366.html">
 290           N4366
 291         </link>
 292       </entry>
 293       <entry align="center"> 6 </entry>
 294       <entry/>
 295     </row>
 296
 297     <row>
 298       <entry> Re-enabling <code>shared_from_this</code></entry>
 299       <entry>
 300         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0033r1.html">
 301         P0033R1
 302         </link>
 303       </entry>
 304       <entry align="center"> 7 </entry>
 305       <entry><code>__cpp_lib_enable_shared_from_this >= 201603</code></entry>
 306     </row>
 307
 308     <row>
 309       <entry> A proposal to add <code>invoke</code> function template </entry>
 310       <entry>
 311         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4169.html">
 312         N4169
 313         </link>
 314       </entry>
 315       <entry align="center"> 6.1 </entry>
 316       <entry><code> __cpp_lib_invoke >= 201411 </code></entry>
 317     </row>
 318
 319     <row>
 320       <entry>TriviallyCopyable <code>reference_wrapper</code> </entry>
 321       <entry>
 322         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4277.html">
 323           N4277
 324         </link>
 325       </entry>
 326       <entry align="center"> 5.1 </entry>
 327       <entry/>
 328     </row>
 329
 330     <row>
 331       <entry> Adopt <code>not_fn</code> from Library Fundamentals 2 for C++17 </entry>
 332       <entry>
 333         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0005r4.html">
 334         P0005R4
 335         </link>
 336       </entry>
 337       <entry align="center"> 7 </entry>
 338       <entry><code>__cpp_lib_not_fn >= 201603</code></entry>
 339     </row>
 340
 341     <row>
 342       <entry> Fixes for <code>not_fn</code> </entry>
 343       <entry>
 344         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0358r1.html">
 345         P0358R1
 346         </link>
 347       </entry>
 348       <entry align="center"> 7 </entry>
 349       <entry/>
 350     </row>
 351
 352     <row>
 353       <entry> Fixing a design mistake in the searchers interface in Library Fundamentals </entry>
 354       <entry>
 355         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0253r1.pdf">
 356         P0253R1
 357         </link>
 358       </entry>
 359       <entry align="center"> 7 </entry>
 360       <entry/>
 361     </row>
 362
 363     <row>
 364       <entry> Extending memory management tools </entry>
 365       <entry>
 366         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0040r3.html">
 367         P0040R3
 368         </link>
 369       </entry>
 370       <entry align="center"> 7 </entry>
 371       <entry><code> </code></entry>
 372     </row>
 373
 374     <row>
 375       <entry> <code>shared_ptr::weak_type</code></entry>
 376       <entry>
 377         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/p0163r0.html">
 378         P0163R0
 379         </link>
 380       </entry>
 381       <entry align="center"> 7 </entry>
 382       <entry><code> __cpp_lib_shared_ptr_weak_type >= 201606</code></entry>
 383     </row>
 384
 385     <row>
 386       <entry>Transformation Trait Alias <code>void_t</code></entry>
 387       <entry>
 388         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/JTC1/sc22/WG21/docs/papers/2014/n3911.pdf">
 389           N3911
 390         </link>
 391       </entry>
 392       <entry align="center">6.1</entry>
 393       <entry><code> __cpp_lib_void_t >= 201411</code></entry>
 394     </row>
 395
 396     <row>
 397       <entry> Wording for <code>bool_constant</code>, revision 1 </entry>
 398       <entry>
 399         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4389.html">
 400           N4389
 401         </link>
 402       </entry>
 403       <entry align="center">6.1</entry>
 404       <entry><code> __cpp_lib_bool_constant >= 201505</code></entry>
 405     </row>
 406
 407     <row>
 408       <entry> Adopt Type Traits Variable Templates from Library Fundamentals TS for C++17</entry>
 409       <entry>
 410         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/p0006r0.html">
 411         P0006R0
 412         </link>
 413       </entry>
 414       <entry align="center"> 7 </entry>
 415       <entry><code> __cpp_lib_type_trait_variable_templates >= 201510 </code></entry>
 416     </row>
 417
 418     <row>
 419       <entry> Logical Operator Type Traits</entry>
 420       <entry>
 421         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/p0013r1.html">
 422         P0013R1
 423         </link>
 424       </entry>
 425       <entry align="center"> 6.1 </entry>
 426       <entry><code> __cpp_lib_logical_traits >= 201510 </code></entry>
 427     </row>
 428
 429     <row>
 430       <entry> Adding [nothrow-]swappable traits </entry>
 431       <entry>
 432         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0185r1.html">
 433         P0185R1
 434         </link>
 435       </entry>
 436       <entry align="center"> 7 (<code>__is_swappable</code> available since 6.1)</entry>
 437       <entry><code> __cpp_lib_is_swappable >= 201603 </code></entry>
 438     </row>
 439
 440     <row>
 441       <entry> <code>is_callable</code>, the missing INVOKE related trait</entry>
 442       <entry>
 443         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0077r2.html">
 444         P0077R2
 445         </link>
 446       </entry>
 447       <entry align="center"> 7 </entry>
 448       <entry><code> __cpp_lib_is_callable >= 201603 </code></entry>
 449     </row>
 450
 451     <row>
 452       <entry> has_unique_object_representations </entry>
 453       <entry>
 454         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0258r2.html">
 455         P0258R2
 456         </link>
 457       </entry>
 458       <entry align="center"> 7 </entry>
 459       <entry><code> __cpp_lib_has_unique_object_representations >= 201606 </code></entry>
 460     </row>
 461
 462     <row>
 463       <entry> Polishing <code>&lt;chrono&gt;</code> </entry>
 464       <entry>
 465         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/p0092r1.html">
 466         P0092R1
 467         </link>
 468       </entry>
 469       <entry align="center"> 7 </entry>
 470       <entry><code> __cpp_lib_chrono >= 201510 </code></entry>
 471     </row>
 472
 473     <row>
 474       <entry> Adding more constexpr to <code>&lt;chrono&gt;</code> </entry>
 475       <entry>
 476         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0505r0.html">
 477         P0505R0
 478         </link>
 479       </entry>
 480       <entry align="center"> 7 </entry>
 481       <entry><code> ??? </code></entry>
 482     </row>
 483
 484     <row>
 485       <?dbhtml bgcolor="#B0B0B0" ?>
 486       <entry> Constexpr for <code>std::char_traits</code> </entry>
 487       <entry>
 488         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0426r1.html">
 489         P0426R1
 490         </link>
 491       </entry>
 492       <entry align="center"> 7 (partial) </entry>
 493       <entry><code> ??? </code></entry>
 494     </row>
 495
 496     <row>
 497       <entry> Integrating <code>std::string_view</code> and <code>std::string</code> </entry>
 498       <entry>
 499         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0254r2.pdf">
 500         P0254R2
 501         </link>
 502       </entry>
 503       <entry align="center"> 7 </entry>
 504       <entry><code> </code></entry>
 505     </row>
 506
 507     <row>
 508       <entry> Give 'std::string' a non-const '.data()' member function </entry>
 509       <entry>
 510         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0272r1.html">
 511         P0272R1
 512         </link>
 513       </entry>
 514       <entry align="center"> 7 </entry>
 515       <entry><code> </code></entry>
 516     </row>
 517
 518     <row>
 519       <entry>Cleaning-up noexcept in the Library</entry>
 520       <entry>
 521         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4258.pdf">
 522           N4258
 523         </link>
 524       </entry>
 525       <entry align="center">6.1</entry>
 526       <entry><code> __cpp_lib_allocator_traits_is_always_equal >= 201411 </code></entry>
 527     </row>
 528
 529     <row>
 530       <entry>Contiguous Iterators </entry>
 531       <entry>
 532         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4284.html">
 533           N4284
 534         </link>
 535       </entry>
 536       <entry align="center">N/A</entry>
 537       <entry/>
 538     </row>
 539
 540     <row>
 541       <entry> Minimal incomplete type support for standard containers </entry>
 542       <entry>
 543         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4510.html">
 544         N4510
 545         </link>
 546       </entry>
 547       <entry align="center"> 6.2 (3.0)</entry>
 548       <entry><code> __cpp_lib_incomplete_container_elements >= 201505 </code>
 549              (the feature was always supported, but the macro was not defined until GCC 6.2)
 550       </entry>
 551     </row>
 552
 553     <row>
 554       <entry> Emplace return type </entry>
 555       <entry>
 556         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0084r2.pdf">
 557         P0084R2
 558         </link>
 559       </entry>
 560       <entry align="center"> 7 </entry>
 561       <entry><code> ??? </code></entry>
 562     </row>
 563
 564     <row>
 565       <entry>Improved insertion interface for unique-key maps</entry>
 566       <entry>
 567         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4279.html">
 568           N4279
 569         </link>
 570       </entry>
 571       <entry align="center"> 6.1 </entry>
 572       <entry><code> __cpp_lib_map_try_emplace >= 201411</code>,
 573              <code> __cpp_lib_unordered_map_try_emplace >= 201411</code>
 574       </entry>
 575     </row>
 576
 577     <row>
 578       <entry> Splicing Maps and Sets </entry>
 579       <entry>
 580         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0083r3.pdf">
 581         P0083R3
 582         </link>
 583       </entry>
 584       <entry align="center"> 7 </entry>
 585       <entry><code> __cpp_lib_node_extract >= 201606 </code></entry>
 586     </row>
 587
 588     <row>
 589       <entry>Non-member <code>size()</code> and more</entry>
 590       <entry>
 591         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4280.pdf">
 592           N4280
 593         </link>
 594       </entry>
 595       <entry align="center"> 6.1 </entry>
 596       <entry><code> __cpp_lib_nonmember_container_access >= 201411 </code></entry>
 597     </row>
 598
 599     <row>
 600       <entry> A Proposal to Add Constexpr Modifiers to <code>reverse_iterator</code>, <code>move_iterator</code>, <code>array</code> and Range Access </entry>
 601       <entry>
 602         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/p0031r0.html">
 603         P0031R0
 604         </link>
 605       </entry>
 606       <entry align="center"> 7 </entry>
 607       <entry><code> __cpp_lib_array_constexpr >= 201603 </code></entry>
 608     </row>
 609
 610     <row>
 611       <?dbhtml bgcolor="#C8B0B0" ?>
 612       <entry> The Parallelism TS Should be Standardized  </entry>
 613       <entry>
 614         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0024r2.html">
 615         P0024R2
 616         </link>
 617       </entry>
 618       <entry align="center"> No </entry>
 619       <entry><code> __has_include(&lt;execution&gt;) </code>,
 620              <code> __cpp_lib_parallel_algorithm >= 201603 </code></entry>
 621     </row>
 622
 623     <row>
 624       <entry> An algorithm to "clamp" a value between a pair of boundary values </entry>
 625       <entry>
 626         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/p0025r0.html">
 627         P0025R0
 628         </link>
 629       </entry>
 630       <entry align="center"> 7 </entry>
 631       <entry><code> __cpp_lib_clamp >= 201603 </code></entry>
 632     </row>
 633
 634     <row>
 635       <entry> Adopt Selected Library Fundamentals V2 Components for C++17 </entry>
 636       <entry>
 637         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0295r0.pdf">
 638         P0295R0
 639         </link>
 640       </entry>
 641       <entry align="center"> 7 </entry>
 642       <entry><code> __cpp_lib_gcd >= 201606 </code>,
 643              <code> __cpp_lib_lcm >= 201606 </code>
 644       </entry>
 645     </row>
 646
 647     <row>
 648       <entry> Proposal to Introduce a 3-Argument Overload to <code>std::hypot</code> </entry>
 649       <entry>
 650         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/p0030r1.pdf">
 651         P0030R1
 652         </link>
 653       </entry>
 654       <entry align="center"> 7 </entry>
 655       <entry><code> __cpp_lib_hypot >= 201603 </code></entry>
 656     </row>
 657
 658     <row>
 659       <entry> Mathematical Special Functions for C++17 </entry>
 660       <entry>
 661         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0226r1.pdf">
 662         P0226R1
 663         </link>
 664       </entry>
 665       <entry align="center"> 7 (6.1) </entry>
 666       <entry><code> __cpp_lib_math_special_functions >= 201603 </code>
 667              (for GCC 6 or pre-C++17 define
 668              <code>__STDCPP_WANT_MATH_SPEC_FUNCS__</code> to a non-zero value
 669              and test for <code>__STDCPP_MATH_SPEC_FUNCS__ >= 201003L</code>)
 670       </entry>
 671     </row>
 672
 673     <row>
 674       <?dbhtml bgcolor="#C8B0B0" ?>
 675       <entry>Adopt the File System TS for C++17  </entry>
 676       <entry>
 677         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0218r1.html">
 678         P0218R1
 679         </link>
 680       </entry>
 681       <entry align="center"> No </entry>
 682       <entry><code> __has_include(&lt;filesystem&gt;) </code>,
 683              <code> __cpp_lib_filesystem >= 201603 </code></entry>
 684     </row>
 685
 686     <row>
 687       <?dbhtml bgcolor="#C8B0B0" ?>
 688       <entry> Relative Paths for Filesystem</entry>
 689       <entry>
 690         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0219r1.html">
 691         P0219R1
 692         </link>
 693       </entry>
 694       <entry align="center"> No </entry>
 695       <entry/>
 696     </row>
 697
 698     <row>
 699       <?dbhtml bgcolor="#C8B0B0" ?>
 700       <entry> Adapting string_view by filesystem paths </entry>
 701       <entry>
 702         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0392r0.pdf">
 703         P0392R0
 704         </link>
 705       </entry>
 706       <entry align="center"> No </entry>
 707       <entry/>
 708     </row>
 709
 710     <row>
 711       <entry> constexpr <code>atomic&lt;T&gt;::is_always_lock_free</code>        </entry>
 712       <entry>
 713         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0152r1.html">
 714         P0152R1
 715         </link>
 716       </entry>
 717       <entry align="center"> 7 </entry>
 718       <entry><code> __cpp_lib_atomic_is_always_lock_free >= 201603 </code></entry>
 719     </row>
 720
 721     <row>
 722       <entry>A proposal to add <code>shared_mutex</code> (untimed) (Revision 4)</entry>
 723       <entry>
 724         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4508.html">
 725           N4508
 726         </link>
 727       </entry>
 728       <entry align="center"> 6.1 </entry>
 729       <entry><code> __cpp_lib_shared_mutex >= 201505 </code></entry>
 730     </row>
 731
 732     <row>
 733       <entry> Variadic <code>lock_guard</code> </entry>
 734       <entry>
 735         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0156r2.html">
 736         P0156R2
 737         </link>
 738       </entry>
 739       <entry align="center"> 7 </entry>
 740       <entry><code> __cpp_lib_scoped_lock >= 201703 </code></entry>
 741     </row>
 742
 743     <row>
 744       <entry> byte type definition </entry>
 745       <entry>
 746         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0298r3.pdf">
 747         P0298R3
 748         </link>
 749       </entry>
 750       <entry align="center"> 7 </entry>
 751       <entry><code> ??? </code></entry>
 752     </row>
 753
 754     <row>
 755       <?dbhtml bgcolor="#C8B0B0" ?>
 756       <entry> Elementary string conversions </entry>
 757       <entry>
 758         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0067r5.html">
 759         P0067R5
 760         </link>
 761       </entry>
 762       <entry align="center"> No </entry>
 763       <entry><code> ??? </code></entry>
 764     </row>
 765
 766
 767   </tbody>
 768 </tgroup>
 769 </table>
 770
 771
 772 <table frame="all" xml:id="table.cxx1z_ts_status">
 773 <title>C++ Technical Specifications Implementation Status</title>
 774
 775 <tgroup cols="4" align="left" colsep="0" rowsep="1">
 776 <colspec colname="c1"/>
 777 <colspec colname="c2"/>
 778 <colspec colname="c3"/>
 779 <colspec colname="c4"/>
 780   <thead>
 781     <row>
 782       <entry>Paper</entry>
 783       <entry>Title</entry>
 784       <entry>Status</entry>
 785       <entry>Comments</entry>
 786     </row>
 787   </thead>
 788
 789   <tbody>
 790
 791     <row>
 792       <entry>
 793         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/JTC1/SC22/WG21/docs/papers/2014/n4076.html">
 794           N4076
 795         </link>
 796       </entry>
 797       <entry>A generalized callable negator</entry>
 798       <entry>Y</entry>
 799       <entry>Library Fundamentals 2 TS</entry>
 800     </row>
 801
 802     <row>
 803       <entry>
 804         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/JTC1/SC22/WG21/docs/papers/2014/n4273.htm">
 805           N4273
 806         </link>
 807       </entry>
 808       <entry>Uniform Container Erasure</entry>
 809       <entry>Y</entry>
 810       <entry>Library Fundamentals 2 TS</entry>
 811     </row>
 812
 813     <row>
 814       <entry>
 815         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4061.pdf">
 816           N4061
 817         </link>
 818       </entry>
 819       <entry>Greatest Common Divisor and Least Common Multiple</entry>
 820       <entry>Y</entry>
 821       <entry>Library Fundamentals 2 TS</entry>
 822     </row>
 823
 824     <row>
 825       <entry>
 826         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4066.htm">
 827           N4066
 828         </link>
 829       </entry>
 830       <entry>Delimited iterators</entry>
 831       <entry>Y</entry>
 832       <entry>Library Fundamentals 2 TS</entry>
 833     </row>
 834
 835     <row>
 836       <entry>
 837         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4282.pdf">
 838           N4282
 839         </link>
 840       </entry>
 841       <entry>The World's Dumbest Smart Pointer</entry>
 842       <entry>Y</entry>
 843       <entry>Library Fundamentals 2 TS</entry>
 844     </row>
 845
 846
 847     <row>
 848       <entry>
 849         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4388.html">
 850           N4388
 851         </link>
 852       </entry>
 853       <entry>Const-Propagating Wrapper</entry>
 854       <entry>Y</entry>
 855       <entry>Library Fundamentals 2 TS</entry>
 856     </row>
 857
 858     <row>
 859       <entry>
 860         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4391.html">
 861           N4391
 862         </link>
 863       </entry>
 864       <entry> <code>make_array</code>, revision 4 </entry>
 865       <entry>Y</entry>
 866       <entry>Library Fundamentals 2 TS</entry>
 867     </row>
 868
 869     <row>
 870       <entry>
 871         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4502.pdf">
 872           N4502
 873         </link>
 874       </entry>
 875       <entry> Support for the C++ Detection Idiom, V2 </entry>
 876       <entry>Y</entry>
 877       <entry>Library Fundamentals 2 TS</entry>
 878     </row>
 879
 880     <row>
 881       <?dbhtml bgcolor="#C8B0B0" ?>
 882       <entry>
 883         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4519.pdf">
 884           N4519
 885         </link>
 886       </entry>
 887       <entry> Source-Code Information Capture </entry>
 888       <entry>N</entry>
 889       <entry>Library Fundamentals 2 TS</entry>
 890     </row>
 891
 892     <row>
 893       <?dbhtml bgcolor="#C8B0B0" ?>
 894       <entry>
 895         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4521.html">
 896           N4521
 897         </link>
 898       </entry>
 899       <entry> Merge Fundamentals V1 into V2 </entry>
 900       <entry>N</entry>
 901       <entry>Library Fundamentals 2 TS</entry>
 902     </row>
 903
 904     <row>
 905       <entry>
 906         <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://open-std.org/JTC1/SC22/WG21/docs/papers/2015/p0013r1.html">
 907           P0013R1
 908         </link>
 909       </entry>
 910       <entry>Logical Operator Type Traits (revision 1)</entry>
 911       <entry>Y</entry>
 912       <entry>Library Fundamentals 2 TS</entry>
 913     </row>
 914
 915
 916   </tbody>
 917 </tgroup>
 918 </table>
 919
 920 <section xml:id="iso.2017.specific" xreflabel="Implementation Specific"><info><title>Implementation Specific Behavior</title></info>
 921
 922    <para>For behaviour which is also specified by previous standards,
 923       see <link linkend="iso.1998.specific">C++ 1998/2003 Implementation
 924       Specific Behavior</link> and <link linkend="iso.2011.specific">C++
 925       2011 Implementation Specific Behavior</link>. This section only
 926       documents behaviour which is new in the 2017 standard.
 927    </para>
 928
 929    <para>
 930       <emphasis>20.6.5 [optional.bad_optional_access]</emphasis>
 931       <code>what()</code> returns <literal>"bad optional access"</literal>.
 932    </para>
 933
 934    <para>
 935       <emphasis>20.7.2 [variant.variant]</emphasis>
 936       Whether <classname>variant</classname> supports over-aligned types
 937       should be documented here.
 938    </para>
 939
 940    <para>
 941       <emphasis>20.7.10 [variant.bad.access]</emphasis>
 942       <code>what()</code> returns <literal>"Unexpected index"</literal>.
 943    </para>
 944
 945    <para>
 946       <emphasis>20.12.5.2 [memory.resource.pool.options]</emphasis>
 947       The limits for maximum number of blocks and largest allocation size
 948       supported by <classname>pool_options</classname> should be documented
 949       here.
 950    </para>
 951
 952    <para>
 953       <emphasis>20.12.6.1 [memory.resource.monotonic.buffer.ctor]</emphasis>
 954       The default <code>next_buffer_size</code> and growth factor should
 955       be documented here.
 956    </para>
 957
 958    <para>
 959       <emphasis>20.15.4.3 [meta.unary.prop]</emphasis>
 960       The predicate condition for
 961       <code>has_unique_object_representations</code> is true for all scalar
 962       types except floating point types.
 963    </para>
 964
 965    <para>
 966       <emphasis>20.19.3 [execpol.type],
 967       25.2.3 [algorithms.parallel.exec]</emphasis>
 968       There are no implementation-defined execution policies.
 969    </para>
 970
 971    <para>
 972       <emphasis>22.4.2 [string.view.template]</emphasis>
 973       <classname>basic_string_view&lt;C, T&gt;::iterator</classname> is
 974       <code>C*</code> and
 975       <classname>basic_string_view&lt;C, T&gt;::const_iterator</classname> is
 976       <code>const C*</code>.
 977    </para>
 978
 979
 980    <para>
 981       <emphasis>25.2.3 [algorithms.parallel.exec]</emphasis>
 982       Threads of execution created by <classname>std::thread</classname>
 983       provide concurrent forward progress guarantees, so threads of execution
 984       implicitly created by the library will provide parallel forward
 985       progress guarantees.
 986    </para>
 987
 988    <para>
 989       <emphasis>26.4.1 [cfenv.syn]</emphasis>
 990       The effects of the <filename>&lt;cfenv&gt;</filename> functions
 991       depends on whether the <code>FENV_ACCESS</code> pragma is supported,
 992       and on the C library that provides the header.
 993    </para>
 994
 995    <para>
 996       <emphasis>26.6.9 [c.math.rand]</emphasis>
 997       Whether the <function>rand</function> function may introduce data
 998       races depends on the target C library that provides the function.
 999    </para>
1000
1001    <para>
1002       <emphasis>26.9.5 [sf.cmath]</emphasis>
1003       The effect of calling the mathematical special functions with large
1004       inputs should be documented here.
1005    </para>
1006
1007    <para>
1008       <emphasis>27.10.2.1 [fs.conform.9945]</emphasis>
1009       The behavior of the filesystem library implementation will depend on
1010       the target operating system. Some features will not be not supported
1011       on some targets.
1012    </para>
1013
1014    <para>
1015       <emphasis>27.10.6 [fs.filesystem.syn]</emphasis>
1016       The clock used for file times is
1017       <classname>std::chrono::system_clock</classname>.
1018    </para>
1019
1020    <para>
1021       <emphasis>27.10.8 [path.generic]</emphasis>
1022       dot-dot in the root-directory refers to the root-directory itself.
1023    </para>
1024
1025
1026 </section>
1027
1028 </section>