libcxx/docs/ReleaseNotes/23.rst

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Libc++ 23.0.0 (In-Progress) Release Notes
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Written by the `Libc++ Team <https://libcxx.llvm.org>`_

.. warning::

   These are in-progress notes for the upcoming libc++ 23.0.0 release.
   Release notes for previous releases can be found on
   `the Download Page <https://releases.llvm.org/download.html>`_.

Introduction
============

This document contains the release notes for the libc++ C++ Standard Library,
part of the LLVM Compiler Infrastructure, release 23.0.0. Here we describe the
status of libc++ in some detail, including major improvements from the previous
release and new feature work. For the general LLVM release notes, see `the LLVM
documentation <https://llvm.org/docs/ReleaseNotes.html>`_. All LLVM releases may
be downloaded from the `LLVM releases web site <https://llvm.org/releases/>`_.

For more information about libc++, please see the `Libc++ Web Site
<https://libcxx.llvm.org>`_ or the `LLVM Web Site <https://llvm.org>`_.

Note that if you are reading this file from a Git checkout or the
main Libc++ web page, this document applies to the *next* release, not
the current one. To see the release notes for a specific release, please
see the `releases page <https://llvm.org/releases/>`_.

What's New in Libc++ 23.0.0?
==============================

Implemented Papers
------------------

Improvements and New Features
-----------------------------

Deprecations and Removals
-------------------------

Potentially breaking changes
----------------------------

Announcements About Future Releases
-----------------------------------

ABI Affecting Changes
---------------------

- ``std::allocator`` is trivially default constructible since LLVM 22. The behaviour can be reverted by defining
  ``_LIBCPP_DEPRECATED_ABI_NON_TRIVIAL_ALLOCATOR``. Please inform the libc++ team if you need this flag, since it will
  be removed in LLVM 24 if there is no evidence that it's required.

- ``bitset::operator[]`` returns ``bool`` since LLVM 22, making libc++ conforming. The behaviour can be reverted by
  defining ``_LIBCPP_DEPRECATED_ABI_BITSET_CONST_SUBSCRIPT_RETURN_REF``. Please inform the libc++ team if you need this
  flag, since it will be removed in LLVM 24 if there is no evidence that it's required.

Build System Changes
--------------------