Python 3.14: Fix, decorators were breaking when disabling deferred annotations. (Fixed in 4.0.1 already.)

Fix, nested loops could have wrong traces lead to mis-optimization. (Fixed in 4.0.1 already.)

Plugins: Fix, run-time check of package configuration was incorrect. (Fixed in 4.0.1 already.)

Compatibility: Fix, __builtins__ lacked necessary compatibility in compiled functions. (Fixed in 4.0.1 already.)

Distutils: Fix, incorrect UTF-8 decoding was used for TOML input file parsing. (Fixed in 4.0.1 already.)

Fix, multiple hard value assignments could cause compile time crashes. (Fixed in 4.0.1 already.)

Fix, string concatenation was not properly annotating exception exits. (Fixed in 4.0.2 already.)

Windows: Fix, --verbose-output and --show-modules-output did not work with forward slashes. (Fixed in 4.0.2 already.)

Python 3.14: Fix, there were various compatibility issues including dictionary watchers and inline values. (Fixed in 4.0.2 already.)

Python 3.14: Fix, stack pointer initialization to localsplus was incorrect to avoid garbage collection issues. (Fixed in 4.0.2 already.)

Python 3.12+: Fix, generic type variable scoping in classes was incorrect. (Fixed in 4.0.2 already.)

Python 3.12+: Fix, there were various issues with function generics. (Fixed in 4.0.2 already.)

Python 3.8+: Fix, names in named expressions were not mangled. (Fixed in 4.0.2 already.)

Plugins: Fix, module checksums were not robust against quoting style of module-name entry in YAML configurations. (Fixed in 4.0.2 already.)

Plugins: Fix, doing imports in queried expressions caused corruption. (Fixed in 4.0.2 already.)

UI: Fix, support for uv_build in the --project option was broken. (Fixed in 4.0.2 already.)

Compatibility: Fix, names assigned in assignment expressions were not mangled. (Fixed in 4.0.2 already.)

Python 3.12+: Fix, there were still various issues with function generics. (Fixed in 4.0.3 already.)

Clang: Fix, debug mode was disabled for clang generally, but only ClangCL and macOS Clang didn’t want it. (Fixed in 4.0.3 already.)

Zig: Fix, --windows-console-mode=attach|disable was not working when using Zig. (Fixed in 4.0.3 already.)

macOS: Fix, yet another way self dependencies can look like, needed to have support added. (Fixed in 4.0.3 already.)

Python 3.12+: Fix, generic types in classes had bugs with multiple type variables. (Fixed in 4.0.3 already.)

Scons: Fix, repeated builds were not producing binary identical results. (Fixed in 4.0.3 already.)

Scons: Fix, compiling with newer Python versions did not fall back to Zig when the developer prompt MSVC was unusable, and error reporting could crash. (Fixed in 4.0.4 already.)

Zig: Fix, the workaround for Windows console mode attach or disable was incorrectly applied on non-Windows platforms. (Fixed in 4.0.4 already.)

Standalone: Fix, linking with Python Build Standalone failed because libHacl_Hash_SHA2 was not filtered out unconditionally. (Fixed in 4.0.4 already.)

Python 3.6+: Fix, exceptions like CancelledError thrown into an async generator awaiting an inner awaitable could be swallowed, causing crashes. (Fixed in 4.0.4 already.)

Fix, not all ordered set modules accepted generators for update. (Fixed in 4.0.5 already.)

Plugins: Disabled warning about rebuilding the pytokens extension module. (Fixed in 4.0.5 already.)

Standalone: Filtered libHacl_Hash_SHA2 from link libs unconditionally. (Fixed in 4.0.5 already.)

Debugging: Disabled unusable unicode consistency checks for Python versions 3.4 to 3.6. (Fixed in 4.0.5 already.)

Python3.12+ Avoided cloning call nodes on class level which caused issues with generic functions in combination with decorators. (Added in 4.0.5 already.)

Python 3.12+: Added support for generic type variables in async def functions. (Added in 4.0.5 already.)

UI: Fix, flushing outputs for prompts was not working in all cases when progress bars were enabled. (Fixed in 4.0.6 already.)

UI: Fix, unused variable warnings were missing at C compile time when using zig as a C compiler. (Fixed in 4.0.6 already.)

Scons: Fix, forced stdout and stderr paths as a feature was broken. (Fixed in 4.0.6 already.)

Fix, replacing a branch did not accurately track shared active variables causing optimization crashes. (Fixed in 4.0.7 already.)

macOS: Fix, failed to remove extended attributes because files need to be made writable first. (Fixed in 4.0.7 already.)

Fix, dict pop and setdefault using with := rewrites lacked exception-exit annotations for un-hashable keys. (Fixed in 4.0.8 already.)

Python 3.13: Fix, the __parameters__ attribute of generic classes was not working. (Fixed in 4.0.8 already.)

Python 3.11+: Fix, starred arguments were not working as type variables. (Fixed in 4.0.8 already.)

Python2: Fix, FileNotFoundError compatibility fallback handling was not working properly. (Fixed in 4.0.8 already.)

Compatibility: Fix, loop ownership check in value traces was missing, causing issues with nested loops.

Windows: Improved --windows-console-mode=attach to properly handle console handles, enabling cases like os.system to work nicely.

Python2: Fix, there was a compatibility issue where providing default values to the mkdtemp function was failing.

Windows: Fix, there were spurious issues with C23 embedding in 32-bit MinGW64 by switching to coff_obj resource mode for it as well.

Plugins: Fix, the post-import-code execution could fail because the triggering sub-package was not yet available in sys.modules.

UI: Fix, listing package DLLs with --list-package-dlls was broken due to recent plugin lifecycle changes.

UI: Fix, --list-package-exe was not working properly on non-Windows platforms failing to detect executable files correctly.

UI: Handled paths starting with {PROGRAM_DIR} the same as a relative path when parsing the --onefile-tempdir-spec option.

Plugins: Followed multiprocessing forkserver changes for newer Python versions.

Python 3.12+: Fix, generic class type parameters handling was incorrect.

Python 3.12: Fix, deferred evaluation of type aliases was failing.

Python 3.12+: Aligned sum built-in float summation with CPython’s compensated sum for better accuracy.

Python 3.10+: Fix, uncompiled coroutine throw() return handling was incorrect, restoring completed coroutine results via StopIteration.value rather than exposing them as ordinary return values to the outer await chain.

Python 3.13+: Fix, uncompiled coroutine cancel()/await suspension handling was incorrect, improved to ensure integration compatibility.

macOS: Made finding create-dmg more robustly by also checking the Homebrew path for Intel and from PATH properly.

Compatibility: Fix, class frames were not exposing frame locals.

UI: Detected static-libpython problems, which affected some forms of Anaconda.

Distutils: Rejected --project mixed with --main arguments as it is not useful.

macOS: Fix, zig from PATH or from ziglang was not being used.

Distutils: Fix, the wrong module-root config value was being checked for uv build backend.

macOS: Fix, was attempting to change removed (rejected) DLLs, which of course failed and errored out.

Python 3.14: Fix, tuple reuse was not fully compatible, potentially causing crashes due to outdated hash caches.

Fix, fake modules were still being attempted to located when imported by other code, which could conflict with existing modules.

Python 3.5+: Fix, failed to send uncompiled coroutines the sent in value in yield from.

Fix, older gcc compilers lacking newer intrinsic methods had compilation issues that needed to be addressed.

Standalone: Fix, multiphase module extension modules with post-load code were not working properly.

Fix, Avoid using the non-inline copy of pkg_resources with the inline copy of Jinja2. These could mismatch and cause errors.

Fix, loops could make releasing of previous values very unclear, causing optimization errors.

Fix, incbin resource mode was not working with old gcc C++ fallback.

Python 3.4 to 3.6: Fix, bytecode demotion was not working properly for these versions, also bytecode only files not working.

Plugins: Added a check for the broken patchelf versions 0.10 and 0.11 to prevent breaking Qt plugins.

Android: Allowed patchelf version 0.18 on Android.

Windows: Fix, the header path for self uninstalled Python was not detected correctly.

Release: Fix, inclusion of the pkg_resources inline copy for Python 2 to source distributions was missing.

UI: Detected the OBS versions of SUSE Linux better.

Suse: Allowed using patchelf 0.18.0 there too.

Python 3.11: Fix, package and module dicts were not aligned close enough to avoid a CPython bug.

Fix, unbound compiled methods could crash when called without an object passed.

Standalone: Fix, multiphase module extension modules with postload. (Fixed in 4.0.8 already.)

Onefile: Fix, while waiting for the child, it may already be terminated.

macOS: Removed existing absolute rpaths for Homebrew and MacPorts.

Python 3.14: Avoided warning in CPython headers.

Python 3.14: Followed allocator changes more closely.

Compatibility: Avoided using pkg_resources for Jinja2 template location for loading.

No-GIL: Applied some bug fixes to get basic things to work.