Features/StaticAnalysisOfCPythonExtensions

From FedoraProject

< Features
Revision as of 19:38, 25 April 2011 by Dmalcolm (Talk | contribs)

Jump to: navigation, search


Contents

Static Analysis of CPython Extensions

Summary

I'm working on a static analysis tool that can detect common mistakes made in Python extension modules written in C. We'll run it on all such code in Fedora, fixing any problems we find, and send the patches to the appropriate upstream projects.

Owner

  • Email: dmalcolm@redhat.com

Current status

  • Targeted release: [[Releases/<number> | Fedora <number> ]]
  • Last updated: 2011-04-25
  • Percentage of completion: 5%


Detailed Description

Python makes it relatively easy to write wrapper code for C and C++ libraries, acting as a "glue" from which programs can be created.

Unfortunately, there are various mistakes that are commonly made in such wrapper code, and these mistakes can lead to /usr/bin/python leaking memory or segfaulting. There are other mistakes that only manifest as bugs when run on less common CPU architectures.

I'm working on static analysis code for C, to detect common errors in C extension modules for Python. The plan is to integrate this with Fedora's packaging, so that all C extension modules packaged for Python 2 and Python 3 can be guaranteed free of such errors (by adding hooks to the python-devel and python3-devel packages). We can also send fixes for this code as needed to upstream projects, when it reports problems.

For this to be viable, we'll need the tool to achieve a good signal:noise ratio.

Benefit to Fedora

Fedora is already a great environment for doing Python development - having a good-quality static analysis tool integrated into Fedora's build system for python extension modules will make Fedora even more compelling for Python developers. (Naturally the tool will be Free Software, and thus usable on other platforms; but we'll have it first).

The presence of the tool should also make it easier to fix certain awkward bugs, and make it easier to support secondary CPU architectures.

Scope

This involves:

  • writing the tool
  • tuning it to achieve a good signal:noise ratio:
    • testing it on a large number of different extension modules
    • analyzing the issues that it reports; fixing bugs in the
  • itegrating it into the python 2 and python 3 build of Fedora RPMs (python-devel and python3-devel)


How To Test

User Experience

Dependencies

Contingency Plan

Documentation

Release Notes

Comments and Discussion