Upcoming Release 4.4

This document outlines the changes for the upcoming Nuitka 4.4 release, serving as a draft changelog. It also includes details on hot-fixes applied to the current stable release, 4.3.1.

It currently covers changes up to version 4.4rc1.

Nuitka Release 4.4 (Draft)

Note

These are the draft release notes for the upcoming Nuitka 4.4 release. A primary goal for this version is to improve Python 3.15 support, with work planned on frame locals proxies as in Python 3.13, optimization of iterator unpacking, and inlining of generator expressions. Development is ongoing, and this documentation might lag slightly behind the latest code changes.

Bug Fixes

  • Fix, when the main module raised an exception during its execution, it was unregistered and released like any other module, although its code objects and functions can still be used afterwards, e.g. by __del__ methods making frames during interpreter finalization, which could crash. The main module is now kept registered and referenced. (Fixed in 4.3.1 already.)

  • Python3: Fix, the __path__ of compiled namespace packages was created with the compile time full name of the package, which does not necessarily match the __name__ the module has at run time, so the namespace path could not find its submodules, e.g. for a nested implicit namespace package inside a compiled package. The module __name__ attribute is now used. (Fixed in 4.3.1 already.)

  • Python 3.14+: Fix, deferred annotations did not account for conditional execution, so annotations in blocks that did not run, e.g. under if TYPE_CHECKING:, were still included in __annotations__, unlike CPython, which only includes such annotations if their assignment registered its index in __conditional_annotations__. The registration is now done at run time and checked when the annotations are created. (Fixed in 4.3.1 already.)

    from typing import TYPE_CHECKING

condition = True

if TYPE_CHECKING:
    checked_only: set

if condition:
    executed: str
else:
    not_executed: bytes

# 4.3: all annotations present in "__annotations__"
# 4.3.1: only annotations of executed statements present

  • Standalone: The Tk version 9 interpreter on Windows is now created with the PATH environment variable temporarily removed, since Tk loads ICU DLLs dynamically and prefers versioned DLLs found in the PATH over the ones included with Windows, which could make the program depend on third party software. (Fixed in 4.3.1 already.)

  • Plugins: Fix, the probe that decides whether compiled methods need cached wrappers to avoid the unlimited API PySide6 via SystemError in signal slots used temporary bound methods, which were not protected from the other bug we normally work around. (Fixed in 4.3.1 already.)

  • Anaconda: Fix, the include/python directory used on Windows by Anaconda and conda-forge Python since version 3.15 was not considered when locating the Python headers, so compilation aborted with a message about an unsupported embeddable distribution. (Fixed in 4.3.1 already.)

  • Module: Fix, the file system paths of loader entries used the package prefix that is added to the runtime name when a compiled unit is loaded as a package, e.g. producing ns/pkg instead of pkg, so data and resource files were looked up at the wrong location. The prefix is now removed for the file system paths. (Fixed in 4.3.1 already.)

Package Support

  • None yet.

New Features

  • Python 3.15+: Added support for module export hooks, where an extension module provides a PyModExport_<name> or PyModExportU_<name> function returning a slots array, which CPython prefers over the PyInit_<name> entry point function, with the meta path based loader checking for it first and falling back to PyInit_. Modules from export hooks are created with PyModule_FromSlotsAndSpec, with a SystemError reported for hooks that fail without setting an exception or raise an unreported one, and a missing export function now gives an ImportError naming both functions that were tried. (Added in 4.3.1 already.)

Optimization

  • Type descriptions are now exported uniformly as pointer variables and declared only in the generated module that uses them, so adding a description no longer changes the shared __constants.h header and thereby avoids rebuilding unrelated modules. (Added in 4.3.1 already.)

Anti-Bloat

  • None yet.

Organizational

  • Debian: Fix, the py2dsc based Debian packaging on mounts that report all files as executable, e.g. container builds using Windows shares, gave the copied Debian config files the executable bit, and debhelper then executed nuitka.install instead of reading it, which failed. The executable permission is now removed from the copied files, keeping only rules executable. (Fixed in 4.3.1 already.)

Tests

  • None yet.

Cleanups

  • None yet.

Summary

This release is currently under active development and is not yet feature-complete.