11 August 2014

Nuitka Release 0.5.4

This is to inform you about the new stable release of Nuitka. It is the extremely compatible Python compiler, “download now”.

This release is aiming at preparatory changes to enable optimization based on SSA analysis, introducing a variable registry, so that variables no longer trace their references to themselves.

Otherwise, MinGW64 support has been added, and lots of bug fixes were made to improve the compatibility.


  • Using new variable registry, now properly detecting actual need for sharing variables. Optimization may discover that it is unnecessary to share a variable, and then it no longer is. This also allows --debug without it reporting unused variable warnings on Python3.

  • Scons startup has been accelerated, removing scans for unused tools, and avoiding making more than one gcc version check.

Bug Fixes

  • Compatibility: In case of unknown encodings, Nuitka was not giving the name of the problematic encoding in the error message. Fixed in already.

  • Submodules with the same name as built-in modules were wrongly shadowed. Fixed in already.

  • Python3: Added implementations of is_package to the meta path based loader.

  • Python3.4: Added find_spec implementation to the meta path based loader for increased compatibility.

  • Python3: Corrections for --debug to work with Python3 and MSVC compiler more often.

  • Fixed crash with --show-scons when no compiler was found. Fixed in already.

  • Standalone: Need to blacklist lib2to3 from standard library as well. Fixed in already.

  • Python3: Adapted to changes in SyntaxError on newer Python releases, there is now a msg that can override reason.

  • Standalone Windows: Preserve sys.executable as it might be used to fork binaries.

  • Windows: The caching of Scons was not arch specific, and files could be used again, even if changing the arch from x86 to x86_64 or back.

  • Windows: On 32 bit Python it can happen that with large number of generators running concurrently (>1500), one cannot be started anymore. Raising an MemoryError now.


  • Added support for MinGW64. Currently needs to be run with PATH environment properly set up.

  • Updated internal version of Scons to 2.3.2, which breaks support for VS 2008, but adds support for VS 2013 and VS 2012. The VS 2013 is now the recommended compiler.

  • Added RPM package and repository for RHEL 7.

  • The output of --show-scons now includes the used compiler, including the MSVC version.

  • Added option --msvc to select the MSVC compiler version to use, which overrides automatic selection of the latest.

  • Added option -python-flag=no_warnings to disable user and deprecation warnings at run time.

  • Repository for Ubuntu Raring was removed, no more supported by Ubuntu.


  • Made technical and logical sharing decisions separate functions and implement them in a dedicated variable registry.

  • The Scons file has seen a major cleanup.


This release is mostly a maintenance release. The Scons integrations has been heavily visited, as has been Python3 and esp. Python3.4 compatibility, and results from the now possible debug test runs.

Standalone should be even more practical now, and MinGW64 is an option for those cases, where MSVC is too slow.