xref: /openbsd-src/gnu/llvm/libcxx/docs/Status/Cxx20.rst (revision 4bdff4bed0e3d54e55670334c7d0077db4170f86)
176d0caaeSpatrick.. _cxx20-status:
276d0caaeSpatrick
376d0caaeSpatrick================================
476d0caaeSpatricklibc++ C++20 Status
576d0caaeSpatrick================================
676d0caaeSpatrick
776d0caaeSpatrick.. include:: ../Helpers/Styles.rst
876d0caaeSpatrick
976d0caaeSpatrick.. contents::
1076d0caaeSpatrick   :local:
1176d0caaeSpatrick
1276d0caaeSpatrick
1376d0caaeSpatrickOverview
1476d0caaeSpatrick================================
1576d0caaeSpatrick
1676d0caaeSpatrickIn July 2017, the C++ standard committee created a draft for the next version of the C++ standard, initially known as "C++2a".
1776d0caaeSpatrickIn September 2020, the C++ standard committee approved this draft, and sent it to ISO for approval as C++20.
1876d0caaeSpatrick
1976d0caaeSpatrickThis page shows the status of libc++; the status of clang's support of the language features is `here <https://clang.llvm.org/cxx_status.html#cxx20>`__.
2076d0caaeSpatrick
2176d0caaeSpatrick.. attention:: Features in unreleased drafts of the standard are subject to change.
2276d0caaeSpatrick
2376d0caaeSpatrickThe groups that have contributed papers:
2476d0caaeSpatrick
2576d0caaeSpatrick-  CWG - Core Language Working group
2676d0caaeSpatrick-  LWG - Library working group
2776d0caaeSpatrick-  SG1 - Study group #1 (Concurrency working group)
2876d0caaeSpatrick
2976d0caaeSpatrick.. note:: "Nothing to do" means that no library changes were needed to implement this change.
3076d0caaeSpatrick
3176d0caaeSpatrick.. _paper-status-cxx20:
3276d0caaeSpatrick
3376d0caaeSpatrickPaper Status
3476d0caaeSpatrick====================================
3576d0caaeSpatrick
3676d0caaeSpatrick.. csv-table::
3776d0caaeSpatrick   :file: Cxx20Papers.csv
3876d0caaeSpatrick   :header-rows: 1
3976d0caaeSpatrick   :widths: auto
4076d0caaeSpatrick
4176d0caaeSpatrick.. note::
4276d0caaeSpatrick
43*4bdff4beSrobert   .. [#note-P0591] P0591: The changes in [mem.poly.allocator.mem] are missing.
44*4bdff4beSrobert   .. [#note-P0645] P0645: The paper is implemented but still marked as an incomplete feature
45*4bdff4beSrobert      (the feature-test macro is not set and the libary is only available when built with ``-fexperimental-library``).
46*4bdff4beSrobert      Not yet implemented LWG-issues will cause API and ABI breakage.
4776d0caaeSpatrick   .. [#note-P0966] P0966: It was previously erroneously marked as complete in version 8.0. See `bug 45368 <https://llvm.org/PR45368>`__.
4876d0caaeSpatrick   .. [#note-P0619] P0619: Only sections D.8, D.9, D.10 and D.13 are implemented. Sections D.4, D.7, D.11, D.12, and D.14 remain undone.
49*4bdff4beSrobert   .. [#note-P0883.1] P0883: shared_ptr and floating-point changes weren't applied as they themselves aren't implemented yet.
50*4bdff4beSrobert   .. [#note-P0883.2] P0883: ``ATOMIC_FLAG_INIT`` was marked deprecated in version 14.0, but was undeprecated with the implementation of LWG3659 in version 15.0.
51*4bdff4beSrobert   .. [#note-P2231] P2231: Optional is complete. The changes to variant haven't been implemented yet.
5276d0caaeSpatrick
5376d0caaeSpatrick.. _issues-status-cxx20:
5476d0caaeSpatrick
5576d0caaeSpatrickLibrary Working Group Issues Status
5676d0caaeSpatrick====================================
5776d0caaeSpatrick
5876d0caaeSpatrick.. csv-table::
5976d0caaeSpatrick   :file: Cxx20Issues.csv
6076d0caaeSpatrick   :header-rows: 1
6176d0caaeSpatrick   :widths: auto
62