PyPy v7.3.3: release of 2.7, 3.6, and 3.7 beta

-The PyPy team is proud to release the version 7.3.3 of PyPy, which includes three different interpreters:

  • PyPy2.7, which is an interpreter supporting the syntax and the features of Python 2.7 including the stdlib for CPython 2.7.18 (updated from the previous version)
  • PyPy3.6: which is an interpreter supporting the syntax and the features of Python 3.6, including the stdlib for CPython 3.6.12 (updated from the previous version).
  • PyPy3.7 beta: which is our second release of an interpreter supporting the syntax and the features of Python 3.7, including the stdlib for CPython 3.7.9. We call this beta quality software, there may be issues about compatibility with new and changed features in CPython 3.7. Please let us know what is broken or missing. We have not implemented the documented changes in the re module, and a few other pieces are also missing. For more information, see the PyPy 3.7 wiki page

The interpreters are based on much the same codebase, thus the multiple release. This is a micro release, all APIs are compatible with the 7.3 releases, but read on to find out what is new.

Several issues exposed in the 7.3.2 release were fixed. Many of them came from the great work ongoing to ship PyPy-compatible binary packages in conda-forge. A big shout out to them for taking this on.

Development of PyPy has moved to This was covered more extensively in this blog post. We have seen an increase in the number of drive-by contributors who are able to use gitlab + mercurial to create merge requests.

The CFFI backend has been updated to version 1.14.3. We recommend using CFFI rather than c-extensions to interact with C, and using cppyy for performant wrapping of C++ code for Python.

A new contributor took us up on the challenge to get windows 64-bit support. The work is proceeding on the win64 branch, more help in coding or sponsorship is welcome. In anticipation of merging this large change, we fixed many test failures on windows.

As always, this release fixed several issues and bugs. We strongly recommend updating. Many of the fixes are the direct result of end-user bug reports, so please continue reporting issues as they crop up.

You can find links to download the v7.3.3 releases here:

We would like to thank our donors for the continued support of the PyPy project. If PyPy is not quite good enough for your needs, we are available for direct consulting work.

We would also like to thank our contributors and encourage new people to join the project. PyPy has many layers and we need help with all of them: PyPy and RPython documentation improvements, tweaking popular modules to run on pypy, or general help with making RPython’s JIT even better. Since the previous release, we have accepted contributions from 2 new contributors, thanks for pitching in.

If you are a python library maintainer and use c-extensions, please consider making a cffi / cppyy version of your library that would be performant on PyPy. In any case both cibuildwheel and the multibuild system support building wheels for PyPy.

What is PyPy?

PyPy is a Python interpreter, a drop-in replacement for CPython 2.7, 3.6, and 3.7. It’s fast (PyPy and CPython 3.7.4 performance comparison) due to its integrated tracing JIT compiler.

We also welcome developers of other dynamic languages to see what RPython can do for them.

This PyPy release supports:

  • x86 machines on most common operating systems (Linux 32/64 bits, Mac OS X 64 bits, Windows 32 bits, OpenBSD, FreeBSD)
  • big- and little-endian variants of PPC64 running Linux,
  • s390x running Linux
  • 64-bit ARM machines running Linux.

PyPy does support ARM 32 bit processors, but does not release binaries.


Changes shared across versions

  • Better support macOSx <= 10.13
  • Use MACOSX_DEPLOYMENT_TARGET from environment, if set, when translating
  • Update stdlib to 2.7.18
  • Add limited support for long double to RPython (issue 3312)
  • Package a .hg_archival.txt in the source tarball. The file was left out of the source tarball after the move to heptapod (issue 3315)
  • Fix a race condition in crypt
  • Update expired certificates used in python testing
  • Always use NT sysconfig scheme on windows (issue 3321)
  • Delay importing os and _codecs until after importing site
  • bpo-35194: Fix a wrong constant in cp932 codec
  • bpo-34794: Fix a leak in Tkinter
  • bpo-33781: audioop: enhance rounding double as int
  • bpo-31893: Simplify select.kqueue object comparison

C-API (cpyext) and c-extensions

  • Check for None in PyLong_AsUnsignedLongLong
  • Dynamically allocate Py_buffer.format if needed (issue 3336_)
  • Fix for readonly flag on PyObject_GetBuffer(<bytes>, view) (issue 3307)

Python 3.6+

  • Fix windows support for using venv inside a venv
  • Support os.sendfile on BSD derivatives (macOSx and freebsd)
  • Fix _socket.sethostname(<bytes>)
  • Fix for modifying self.__dict__ in self.__set_name__, issue 3326
  • bpo-33041: Fixed jumping if the function contains an async for loop.
  • bpo-17288: Prevent jump from a yield statement
  • bpo-11471: avoid generating a JUMP_FORWARD instruction at the end of an if-block if there is no else-clause
  • Fix os.listdir('') and os.stat('') on windows (issue 3331)
  • Fix many unicode encoding/decoding errors on windows
  • Fix pickling of time subclasses (issue 3324, bpo-41966)
  • Add support for sqlite3_load_extension (issue 3334)
  • Change default file encoding from mbcs to utf-8 on windows
  • Change default file encoding from ascii to utf-8 on linux
  • Add resource.prlimit()
  • Accept PathLike in nt._getfullpathname (issue 3343)
  • Fix some problems with winreg

Python 3.6 C-API

  • Export PyStructSequence_NewType (issue 3346)