Contributing.rst revision 1.1.1.1.2.2
1 1.1.1.1.2.2 cjep .. _ContributingToLibcxx: 2 1.1.1.1.2.2 cjep 3 1.1.1.1.2.2 cjep ====================== 4 1.1.1.1.2.2 cjep Contributing to libc++ 5 1.1.1.1.2.2 cjep ====================== 6 1.1.1.1.2.2 cjep 7 1.1.1.1.2.2 cjep .. contents:: 8 1.1.1.1.2.2 cjep :local: 9 1.1.1.1.2.2 cjep 10 1.1.1.1.2.2 cjep Please read `this document <https://www.llvm.org/docs/Contributing.html>`__ on general rules to contribute to LLVM projects. 11 1.1.1.1.2.2 cjep 12 1.1.1.1.2.2 cjep Tasks and processes 13 1.1.1.1.2.2 cjep =================== 14 1.1.1.1.2.2 cjep 15 1.1.1.1.2.2 cjep This file contains notes about various tasks and processes specific to libc++. 16 1.1.1.1.2.2 cjep 17 1.1.1.1.2.2 cjep Looking for pre-existing reviews 18 1.1.1.1.2.2 cjep ================================ 19 1.1.1.1.2.2 cjep 20 1.1.1.1.2.2 cjep Before you start working on any feature, please take a look at the open reviews 21 1.1.1.1.2.2 cjep to avoid duplicating someone else's work. You can do that by going to the website 22 1.1.1.1.2.2 cjep where code reviews are held, `Differential <https://reviews.llvm.org/differential>`__, 23 1.1.1.1.2.2 cjep and clicking on ``Libc++ Open Reviews`` in the sidebar to the left. If you see 24 1.1.1.1.2.2 cjep that your feature is already being worked on, please consider chiming in instead 25 1.1.1.1.2.2 cjep of duplicating work! 26 1.1.1.1.2.2 cjep 27 1.1.1.1.2.2 cjep Post-Release TODO 28 1.1.1.1.2.2 cjep ================= 29 1.1.1.1.2.2 cjep 30 1.1.1.1.2.2 cjep After branching for an LLVM release: 31 1.1.1.1.2.2 cjep 32 1.1.1.1.2.2 cjep 1. Update ``_LIBCPP_VERSION`` in ``include/__config`` 33 1.1.1.1.2.2 cjep 2. Update the ``include/__libcpp_version`` file 34 1.1.1.1.2.2 cjep 3. Update the version number in ``docs/conf.py`` 35 1.1.1.1.2.2 cjep 36 1.1.1.1.2.2 cjep Modifying feature-test macros 37 1.1.1.1.2.2 cjep ============================= 38 1.1.1.1.2.2 cjep 39 1.1.1.1.2.2 cjep When adding or updating feature-test macros, you should update the corresponding tests. 40 1.1.1.1.2.2 cjep To do that, modify ``feature_test_macros`` table in the script 41 1.1.1.1.2.2 cjep ``utils/generate_feature_test_macro_components.py``, run it, and commit updated 42 1.1.1.1.2.2 cjep files. Running ``utils/generate_feature_test_macro_components.py`` should never 43 1.1.1.1.2.2 cjep generate diffs in a clean checkout; feel free to run it in your local checkout 44 1.1.1.1.2.2 cjep any time you want. 45 1.1.1.1.2.2 cjep 46 1.1.1.1.2.2 cjep 47 1.1.1.1.2.2 cjep Adding a new header TODO 48 1.1.1.1.2.2 cjep ======================== 49 1.1.1.1.2.2 cjep 50 1.1.1.1.2.2 cjep When adding a new header to libc++: 51 1.1.1.1.2.2 cjep 52 1.1.1.1.2.2 cjep 1. Add a test under ``test/libcxx`` that the new header defines ``_LIBCPP_VERSION``. See ``test/libcxx/algorithms/version.pass.cpp`` for an example. 53 1.1.1.1.2.2 cjep 2. Run ``python utils/generate_header_tests.py``; verify and commit the changes. 54 1.1.1.1.2.2 cjep 3. Modify ``python utils/generate_header_inclusion_tests.py``; run it; verify and commit the changes. 55 1.1.1.1.2.2 cjep 4. Create a submodule in ``include/module.modulemap`` for the new header. 56 1.1.1.1.2.2 cjep 5. Update the ``include/CMakeLists.txt`` file to include the new header. 57 1.1.1.1.2.2 cjep 58 1.1.1.1.2.2 cjep Exporting new symbols from the library 59 1.1.1.1.2.2 cjep ====================================== 60 1.1.1.1.2.2 cjep 61 1.1.1.1.2.2 cjep When exporting new symbols from libc++, you must update the ABI lists located in ``lib/abi``. 62 1.1.1.1.2.2 cjep To test whether the lists are up-to-date, please run the target ``check-cxx-abilist``. 63 1.1.1.1.2.2 cjep To regenerate the lists, use the target ``generate-cxx-abilist``. 64 1.1.1.1.2.2 cjep The ABI lists must be updated for all supported platforms; currently Linux and 65 1.1.1.1.2.2 cjep Apple. If you don't have access to one of these platforms, you can download an 66 1.1.1.1.2.2 cjep updated list from the failed build at 67 1.1.1.1.2.2 cjep `Buildkite <https://buildkite.com/llvm-project/libcxx-ci>`__. 68 1.1.1.1.2.2 cjep Look for the failed build and select the ``artifacts`` tab. There, download the 69 1.1.1.1.2.2 cjep abilist for the platform, e.g.: 70 1.1.1.1.2.2 cjep 71 1.1.1.1.2.2 cjep * C++20 for the Linux platform. 72 1.1.1.1.2.2 cjep * MacOS C++20 for the Apple platform. 73
Indexes created Mon Apr 20 00:23:12 UTC 2026