cpre

cpre analyzes Boolean conditions in C and C++ preprocessor conditional blocks without preprocessing or parsing the surrounding source code. It identifies dead and redundant branches, simplifies Boolean conditions using ROBDD-backed reasoning, and preserves value-bearing expressions as opaque Boolean predicates.

Installation

python -m pip install cpre

For development:

git clone https://github.com/sahebbiswas/cpre.git
cd cpre
python -m pip install -e ".[dev]"

Usage

After installation, run:

cpre source.c

Or invoke the module directly:

python -m cpre.cpre source.c

Useful options include:

--recursive          recursively scan C/C++ source files under directories
--json               emit JSON output
--verbose            include unchanged conditional branches
--fail-on-findings   exit with status 1 when dead or redundant branches are found

By default, text and JSON reports are filtered to branches that are dead, redundant, or whose condition can be simplified. --verbose restores the full conditional tree.

Python API

The analyzer implementation currently lives in cpre/cpre.py and can be imported as:

from cpre import cpre

tree = cpre.analyze_source(source_text)

The initial package layout intentionally preserves the analyzer implementation while establishing a reusable Python package boundary. Public API refinement can follow independently.

Development

Run the test suite with:

pytest

The CI workflow runs the tests across supported Python versions on Linux, macOS, and Windows.

Versioning

The package version is defined once in cpre/__init__.py as __version__ and is consumed by pyproject.toml during builds. The initial version is 0.1.0.

Publishing releases

Publishing to PyPI is handled by .github/workflows/release.yml using PyPI Trusted Publishing. The workflow runs whenever a GitHub release is published, builds both source and wheel distributions, and publishes them to PyPI without a stored API token.

Before the first release, configure a PyPI Trusted Publisher for this repository with:

• Owner: sahebbiswas
• Repository: cpre
• Workflow: release.yml
• Environment: pypi

Create a GitHub Actions environment named pypi as well. It can optionally require approval before deployment.

Before publishing a release, update cpre/__init__.py to the release version and create the GitHub release from a matching tag. Both 0.1.0 and v0.1.0 tag forms are accepted for version 0.1.0; a mismatch causes the publish workflow to fail before uploading anything.

License

Licensed under the Apache License, Version 2.0. See LICENSE.