ValueError: unmarshallable object in PyInstaller 5.4+

[Joe R.]

Hello,

I'm a current developer of PySolFC.  We've been using an AppVeyor script to run PyInstaller to generate our Windows and Max installers, but when we updated to PyInstaller 5.4, the script stopped working.  It ran up to the point where it's "Looking for dynamic libraries", and then fails with a "ValueError: unmarshallable object".

Here is a copy of the most recent run of the AppVeyor script - the error can be seen at the bottom: https://ci.appveyor.com/project/joeraz/pysolfc/builds/46546048#L1389

The AppVeyor script itself is here: https://github.com/joeraz/PySolFC/blob/feature/python-311-installer-test-2/.appveyor.yml

As a workaround, I had set up the script to use PyInstaller 5.3, but I'd like to get the main codebase updated to use Python 3.11, which needs a newer version.

Unfortunately, I didn't write this script.  The people with the PyInstaller know-how to resolve this issue are not currently active on the project.  I really only know the basics myself, so I haven't had much luck debugging this.  Would anyone here be able to assist?  Thanks.

[bwoodsend]

There's been a fair bit of code churn surrounding that part of Windows DLL discovery so first dumb question would just be could you try with the latest PyInstaller? Failing that, you'll probably need to get a print statement in where that exception is being raised to see what exactly it is that it's trying to marshal. My guess would be a pathlib.Path object.

[Joe R.]

Hello,

I did try with the latest version, and got the same results.  5.4 is just the first version that's failing in this way.

[bwoodsend]

That one’s a bug in PyInstaller. I’ve just raised it: https://github.com/pyinstaller/pyinstaller/issues/7515

If you can get six out of your dependency tree, that ought to get you around the problem in the meantime.

​

[Joe R.]

Got it, thanks.