Contributing to the libc Project

LLVM’s libc is being developed as part of the LLVM project so contributions to the libc project should also follow the general LLVM contribution guidelines. Below is a list of open projects that one can start with:

  1. Beginner Bugs - Help us tackle good first issues. These bugs have been tagged with the github labels “libc” and “good first issue” by the team as potentially easier places to get started. Please do first check if the bug has an assignee; if so please find another unless there’s been no movement on the issue from the assignee, in which place do ask if you can help take over.

  2. Cleanup code-style - The libc project follows the general LLVM style but differs in a few aspects: We use snake_case for non-constant variable and function names,``CamelCase`` for internal type names (those which are not defined in a public header), and CAPITALIZED_SNAKE_CASE for constants. When we started working on the project, we started using the general LLVM style for everything. However, for a short period, we switched to the style that is currently followed by the LLD project. But, considering that we implement a lot of functions and types whose names are prescribed by the standards, we have settled on the style described above. However, we have not switched over to this style in all parts of the libc directory. So, a simple but mechanical project would be to move the parts following the old styles to the new style.

  3. Integrating with the rest of the LLVM project - There are two parts to this project:

    1. One is about adding CMake facilities to optionally link the libc’s overlay static archive (see Overlay Mode) with other LLVM tools/executables.

    2. The other is about putting plumbing in place to release the overlay static archive (see Overlay Mode) as part of the LLVM binary releases.

  4. Implement Linux syscall wrappers - A large portion of the POSIX API can be implemented as syscall wrappers on Linux. A good number have already been implemented but many more are yet to be implemented. So, a project of medium complexity would be to implement syscall wrappers which have not yet been implemented.

  5. Add a better random number generator - The current random number generator has a very small range. This has to be improved or switched over to a fast random number generator with a large range.

  6. Update the clang-tidy lint rules and use them in the build and/or CI - Currently, the LLVM libc clang-tidy checks have gone stale and are mostly unused by the developers and on the CI builders. This project is about updating them and reintegrating them back with the build and running them on the CI builders.

  7. double and higher precision math functions - These are under active development but you can take a shot at those not yet implemented. See Math Functions for more information.

  8. Contribute a new OS/Architecture port - You can contribute a new operating system or target architecture port. See Bringup on a New OS or Architecture for more information.