clangir 0.3.1

C/C++ header parsing toolkit with IR, libclang backend, and CFFI writer

clangir

C Intermediate Representation - a Python library for parsing C/C++ headers.

Full documentation: https://axiomantic.github.io/clangir/

Provides an IR data model for parsed C/C++ declarations, a libclang parser backend, and a CFFI cdef writer.

Installation

Requires Python 3.10+.

pip install clangir

System Requirements

libclang shared library must be installed:

• macOS: brew install llvm or Xcode Command Line Tools
• Ubuntu: sudo apt install libclang-dev
• Fedora: sudo dnf install clang-devel
• Windows: Download the LLVM installer or winget install LLVM.LLVM

Supports LLVM 18, 19, 20, and 21. The appropriate version is detected automatically.

Usage

from clangir.backends import get_backend
from clangir.writers.cffi import header_to_cffi

backend = get_backend("libclang")
header = backend.parse('#include "mylib.h"', "wrapper.h", include_dirs=["/path/to/include"])
cdef = header_to_cffi(header)
print(cdef)

This produces CFFI-compatible C declarations that can be passed to ffi.cdef():

struct MyStruct {
    int field;
    ...
};
void my_function(int arg);

Development

git clone https://github.com/axiomantic/clangir.git
cd clangir
pip install -e '.[dev]'
pytest

License

This project is licensed under the MIT License.

The vendored clang Python bindings in clangir/_clang/v*/ are from the LLVM Project and are licensed under the Apache License v2.0 with LLVM Exceptions.