forked from OSchip/llvm-project
89 lines
4.5 KiB
ReStructuredText
89 lines
4.5 KiB
ReStructuredText
.. _ContributingToLibcxx:
|
|
|
|
======================
|
|
Contributing to libc++
|
|
======================
|
|
|
|
This file contains notes about various tasks and processes specific to contributing
|
|
to libc++. If this is your first time contributing, please also read `this document
|
|
<https://www.llvm.org/docs/Contributing.html>`__ on general rules for contributing to LLVM.
|
|
|
|
For libc++, please make sure you follow `these instructions <https://www.llvm.org/docs/Phabricator.html#requesting-a-review-via-the-command-line>`_
|
|
for submitting a code review from the command-line using ``arc``, since we have some
|
|
automation (e.g. CI) that depends on the review being submitted that way.
|
|
|
|
If you plan on contributing to libc++, it can be useful to join the ``#libcxx`` channel
|
|
on `LLVM's Discord server <https://discord.gg/jzUbyP26tQ>`__.
|
|
|
|
Looking for pre-existing reviews
|
|
================================
|
|
|
|
Before you start working on any feature, please take a look at the open reviews
|
|
to avoid duplicating someone else's work. You can do that by going to the website
|
|
where code reviews are held, `Differential <https://reviews.llvm.org/differential>`__,
|
|
and clicking on ``Libc++ Open Reviews`` in the sidebar to the left. If you see
|
|
that your feature is already being worked on, please consider chiming in instead
|
|
of duplicating work!
|
|
|
|
Pre-commit check list
|
|
=====================
|
|
|
|
Before committing or creating a review, please go through this check-list to make
|
|
sure you don't forget anything:
|
|
|
|
- Do you have tests for every public class and/or function you're adding or modifying?
|
|
- Did you update the synopsis of the relevant headers?
|
|
- Did you update the relevant files to track implementation status (in ``docs/Status/``)?
|
|
- Did you mark all functions and type declarations with the :ref:`proper visibility macro <visibility-macros>`?
|
|
- If you added a header:
|
|
|
|
- Did you add it to ``include/module.modulemap.in``?
|
|
- Did you add it to ``include/CMakeLists.txt``?
|
|
- If it's a public header, did you add a test under ``test/libcxx`` that the new header defines ``_LIBCPP_VERSION``? See ``test/libcxx/algorithms/version.pass.cpp`` for an example. NOTE: This should be automated.
|
|
- If it's a public header, did you update ``utils/generate_header_inclusion_tests.py``?
|
|
|
|
- Did you add the relevant feature test macro(s) for your feature? Did you update the ``generate_feature_test_macro_components.py`` script with it?
|
|
- Did you run the ``libcxx-generate-files`` target and verify its output?
|
|
|
|
The review process
|
|
==================
|
|
|
|
After uploading your patch, you should see that the "libc++" review group is automatically
|
|
added as a reviewer for your patch. Once the group is marked as having approved your patch,
|
|
you can commit it. However, if you get an approval very quickly for a significant patch,
|
|
please try to wait a couple of business days before committing to give the opportunity for
|
|
other reviewers to chime in. If you need someone else to commit the patch for you, please
|
|
mention it and provide your ``Name <email@domain>`` for us to attribute the commit properly.
|
|
|
|
Note that the rule for accepting as the "libc++" review group is to wait for two members
|
|
of the group to have approved the patch, excluding the patch author. This is not a hard
|
|
rule -- for very simple patches, use your judgement. The `"libc++" review group <https://reviews.llvm.org/project/members/64/>`__
|
|
consists of frequent libc++ contributors with a good understanding of the project's
|
|
guidelines -- if you would like to be added to it, please reach out on Discord.
|
|
|
|
Post-release check list
|
|
=======================
|
|
|
|
After branching for an LLVM release:
|
|
|
|
1. Update ``_LIBCPP_VERSION`` in ``libcxx/include/__config``
|
|
2. Update the version number in ``libcxx/docs/conf.py``
|
|
3. Update ``_LIBCPPABI_VERSION`` in ``libcxxabi/include/cxxabi.h``
|
|
4. Update ``_LIBUNWIND_VERSION`` in ``libunwind/include/__libunwind_config.h``
|
|
|
|
Exporting new symbols from the library
|
|
======================================
|
|
|
|
When exporting new symbols from libc++, you must update the ABI lists located in ``lib/abi``.
|
|
To test whether the lists are up-to-date, please run the target ``check-cxx-abilist``.
|
|
To regenerate the lists, use the target ``generate-cxx-abilist``.
|
|
The ABI lists must be updated for all supported platforms; currently Linux and
|
|
Apple. If you don't have access to one of these platforms, you can download an
|
|
updated list from the failed build at
|
|
`Buildkite <https://buildkite.com/llvm-project/libcxx-ci>`__.
|
|
Look for the failed build and select the ``artifacts`` tab. There, download the
|
|
abilist for the platform, e.g.:
|
|
|
|
* C++20 for the Linux platform.
|
|
* MacOS C++20 for the Apple platform.
|