Libc++ 21.0.0 (In-Progress) Release Notes¶

Warning

These are in-progress notes for the upcoming libc++ 20.0.0 release. Release notes for previous releases can be found on the Download Page.

Introduction ¶

This document contains the release notes for the libc++ C++ Standard Library, part of the LLVM Compiler Infrastructure, release 20.0.0. 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. All LLVM releases may be downloaded from the LLVM releases web site.

For more information about libc++, please see the Libc++ Web Site or the LLVM Web Site.

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.

What’s New in Libc++ 21.0.0?¶

Implemented Papers ¶

N4258: Cleaning-up noexcept in the Library (Github)

Improvements and New Features ¶

The std::ranges::{copy, copy_n, copy_backward} algorithms have been optimized for std::vector<bool>::iterators, resulting in a performance improvement of up to 2000x.

libc++ documentation