docs/ReleaseNotes.rst

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Libc++ 8.0.0 (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++ 8 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 8.0.0. 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 Subversion 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++ 8.0.0?
===========================

New Features
------------

API Changes
-----------
- Building libc++ for Mac OSX 10.6 is not supported anymore.
- Starting with LLVM 8.0.0, users that wish to link together translation units
  built with different versions of libc++'s headers into the same final linked
  image MUST define the _LIBCPP_HIDE_FROM_ABI_PER_TU macro to 1 when building
  those translation units. Not defining _LIBCPP_HIDE_FROM_ABI_PER_TU to 1 and
  linking translation units built with different versions of libc++'s headers
  together may lead to ODR violations and ABI issues. On the flipside, code
  size improvements should be expected for everyone not defining the macro.