Cura crashes on project saving and material creation.

[a123qwertz567]

Application version

• 4.7.1 (from manjaro repos)
• 4.8 (Appimage from Cura website)
• 4.8 (git version installed via arch AUR)
• 4.6.2 as an Appimage seems to work for now. Saving a project makes it hang/lag for some seconds but it works for now.

Platform Linux-5.9.16-1-Manjaro-x86_64-with-glibc2.32 (tested a 5.6 Kernel, too. No change) Qt version: 5.15.2 PyTw version: 5.12.2 OpenGL Version: 4.6 (Core Profile) Mesa 20.3.1 OpenGL Vendor: AMD OpenGl-Renderer: AMD Radeon (TM) RX 480 Graphics

Printer I tested multiple printers:

• Custom FFF printer (from Ultimaker)
• Sapphire Pro (With custom mesh and config, placed inside curas config folder)

Reproduction steps

• Save project file does not work.
• I have no clear way to reproduce it.
• I think it can be related to the nozzle size parameter and the diameter of the filament set in the printer settings

Screenshot(s) In the screenshot you can see the saving dialog before the crash. What makes me thinking is, there is no value for the nozzle in the extruder section. Maybe this value is mising? This could be connected to the error traceback "TypeError: start expected 2 arguments, got 1"

Actual results

• When I create a new printer and new material and try to save the project cura crashes.
• I can not change the nozzle size of a printer in the settings. Cura does not auto save the change and when I save manually it crashes.

Expected results

• No crash.
• Change nozzle size

Project file (For slicing bugs, provide a project which clearly shows the bug, by going to File->Save Project. For big files you may need to use WeTransfer or similar file sharing sites. G-code files are not project files!)

Log file Error traceback: Traceback (most recent call last): File "/usr/lib/python3.9/site-packages/cura/CuraApplication.py", line 1060, in event return super().event(event) File "/usr/lib/python3.9/site-packages/UM/Qt/QtApplication.py", line 464, in event event._function_event.call() File "/usr/lib/python3.9/site-packages/UM/Event.py", line 218, in call self._function(*self._args, *self._kwargs) File "/usr/lib/python3.9/site-packages/cura/Utils/Threading.py", line 34, in _handle_call ico.result = func(args, **kwargs) File "/usr/lib/cura/plugins/3MFWriter/ThreeMFWorkspaceWriter.py", line 57, in write self._writeContainerToArchive(container, archive) File "/usr/lib/cura/plugins/3MFWriter/ThreeMFWorkspaceWriter.py", line 150, in _writeContainerToArchive serialized_data = container.serialize(ignored_metadata_keys = ignore_keys) File "/usr/lib/cura/plugins/XmlMaterialProfile/XmlMaterialProfile.py", line 154, in serialize builder.start("metadata") # type: ignore TypeError: start expected 2 arguments, got 1

Log: Thread 0x00007f186ffff640 (most recent call first): File "/usr/lib/python3.9/threading.py", line 316 in wait File "/usr/lib/python3.9/site-packages/zeroconf/init.py", line 2432 in wait File "/usr/lib/python3.9/site-packages/zeroconf/init.py", line 1726 in run File "/usr/lib/python3.9/threading.py", line 954 in _bootstrap_inner File "/usr/lib/python3.9/threading.py", line 912 in _bootstrap

Thread 0x00007f1890a79640 (most recent call first): File "/usr/lib/python3.9/threading.py", line 316 in wait File "/usr/lib/python3.9/threading.py", line 574 in wait File "/usr/lib/cura/plugins/UM3NetworkPrinting/src/Network/ZeroConfClient.py", line 81 in _handleOnServiceChangedRequests File "/usr/lib/python3.9/threading.py", line 892 in run File "/usr/lib/python3.9/threading.py", line 954 in _bootstrap_inner File "/usr/lib/python3.9/threading.py", line 912 in _bootstrap

Thread 0x00007f189127a640 (most recent call first): File "/usr/lib/python3.9/threading.py", line 316 in wait File "/usr/lib/python3.9/site-packages/zeroconf/init.py", line 1476 in run File "/usr/lib/python3.9/threading.py", line 954 in _bootstrap_inner File "/usr/lib/python3.9/threading.py", line 912 in _bootstrap

Thread 0x00007f1891a7b640 (most recent call first): File "/usr/lib/python3.9/site-packages/zeroconf/init.py", line 1350 in run File "/usr/lib/python3.9/threading.py", line 954 in _bootstrap_inner File "/usr/lib/python3.9/threading.py", line 912 in _bootstrap

Thread 0x00007f189227c640 (most recent call first): File "/usr/lib/cura/plugins/USBPrinting/USBPrinterOutputDeviceManager.py", line 87 in _updateThread File "/usr/lib/python3.9/threading.py", line 892 in run File "/usr/lib/python3.9/threading.py", line 954 in _bootstrap_inner File "/usr/lib/python3.9/threading.py", line 912 in _bootstrap

Thread 0x00007f1892a7d640 (most recent call first): File "/usr/lib/cura/plugins/RemovableDriveOutputDevice/RemovableDrivePlugin.py", line 61 in _updateThread File "/usr/lib/python3.9/threading.py", line 892 in run File "/usr/lib/python3.9/threading.py", line 954 in _bootstrap_inner File "/usr/lib/python3.9/threading.py", line 912 in _bootstrap

Thread 0x00007f18937fe640 (most recent call first): File "/usr/lib/python3.9/site-packages/UM/Backend/Backend.py", line 165 in _storeStderrToLogThread File "/usr/lib/python3.9/threading.py", line 892 in run File "/usr/lib/python3.9/threading.py", line 954 in _bootstrap_inner File "/usr/lib/python3.9/threading.py", line 912 in _bootstrap

Thread 0x00007f1893fff640 (most recent call first): File "/usr/lib/python3.9/site-packages/UM/Backend/Backend.py", line 153 in _storeOutputToLogThread File "/usr/lib/python3.9/threading.py", line 892 in run File "/usr/lib/python3.9/threading.py", line 954 in _bootstrap_inner File "/usr/lib/python3.9/threading.py", line 912 in _bootstrap

Thread 0x00007f18cbfff640 (most recent call first): File "/usr/lib/python3.9/threading.py", line 312 in wait File "/usr/lib/python3.9/threading.py", line 574 in wait File "/usr/lib/python3.9/site-packages/cura/Utils/Threading.py", line 39 in _call_on_qt_thread_wrapper File "/usr/lib/python3.9/site-packages/UM/FileHandler/WriteFileJob.py", line 76 in run File "/usr/lib/python3.9/site-packages/UM/JobQueue.py", line 132 in run File "/usr/lib/python3.9/threading.py", line 954 in _bootstrap_inner File "/usr/lib/python3.9/threading.py", line 912 in _bootstrap

Thread 0x00007f18d0ff9640 (most recent call first): File "/usr/lib/python3.9/threading.py", line 312 in wait File "/usr/lib/python3.9/threading.py", line 443 in acquire File "/usr/lib/python3.9/site-packages/UM/JobQueue.py", line 98 in _nextJob File "/usr/lib/python3.9/site-packages/UM/JobQueue.py", line 123 in run File "/usr/lib/python3.9/threading.py", line 954 in _bootstrap_inner File "/usr/lib/python3.9/threading.py", line 912 in _bootstrap

Thread 0x00007f18d17fa640 (most recent call first): File "/usr/lib/python3.9/threading.py", line 312 in wait File "/usr/lib/python3.9/threading.py", line 443 in acquire File "/usr/lib/python3.9/site-packages/UM/JobQueue.py", line 98 in _nextJob File "/usr/lib/python3.9/site-packages/UM/JobQueue.py", line 123 in run File "/usr/lib/python3.9/threading.py", line 954 in _bootstrap_inner File "/usr/lib/python3.9/threading.py", line 912 in _bootstrap

Thread 0x00007f18d1ffb640 (most recent call first): File "/usr/lib/python3.9/threading.py", line 312 in wait File "/usr/lib/python3.9/threading.py", line 443 in acquire File "/usr/lib/python3.9/site-packages/UM/JobQueue.py", line 98 in _nextJob File "/usr/lib/python3.9/site-packages/UM/JobQueue.py", line 123 in run File "/usr/lib/python3.9/threading.py", line 954 in _bootstrap_inner File "/usr/lib/python3.9/threading.py", line 912 in _bootstrap

Current thread 0x00007f190bc14740 (most recent call first): File "/usr/lib/python3.9/site-packages/cura/CrashHandler.py", line 393 in _logInfoWidget File "/usr/lib/python3.9/site-packages/cura/CrashHandler.py", line 182 in createDialog File "/usr/lib/python3.9/site-packages/cura/CrashHandler.py", line 86 in init File "/bin/cura", line 166 in exceptHook File "/usr/lib/python3.9/site-packages/UM/Qt/QtApplication.py", line 378 in exec File "/usr/lib/python3.9/site-packages/cura/CuraApplication.py", line 844 in run File "/bin/cura", line 234 in

Additional information

• I updated my system today and switch from a 5.7 kernel to a 5.9 kernel. With the update came lot of python updates, too.
• Could this be pyhton related?
• I reseted and purged cura completely from my PC and installed multiple versions.
• I can export gcode and slice just saving is not possible.

[a123qwertz567]

Workaround for now: I can load a old profile with all settings and slice in that setting. But I cannot save stuff....

[a123qwertz567]

Updated the issue. Cura 4.6 as an Appimage seems to work for now. Saving a project makes it hang/lag for some seconds but it works for now.

[delaosa]

Same crash with AUR package (cura-4.8.0-1) in Arch however 4.8.0 Appimage is working well.

[Ghostkeeper]

Cura currently requires Python 3.5. Perhaps this is one of the places where Python's interface changed to not be backwards compatible? That would explain why it works through the AppImage. We don't support any other Python version.

The line in question is here:

https://github.com/Ultimaker/Cura/blob/9562dc01f47bc1b3a368fa80563677a914bb09a0/plugins/XmlMaterialProfile/XmlMaterialProfile.py#L154

That #type: ignore makes me a bit suspicious that the argument list was also seen as wrong on some computers but correct in the Python version that Cura runs with.

[ayghri]

The problem is in the file "/usr/lib/cura/plugins/XmlMaterialProfile/XmlMaterialProfile.py" You just have to replace all calls: builder.start(X) by builder.start(X,{}) There are a few such calls between line 154 and 196

[delaosa]

Thanks @aghriss, it works for me.

[c24w]

The problem is in the file "/usr/lib/cura/plugins/XmlMaterialProfile/XmlMaterialProfile.py" You just have to replace all calls: builder.start(X) by builder.start(X,{}) There are a few such calls between line 154 and 196

Thanks @aghriss; works for me. Here's a command to do it in one go:

sed -i 's/\(builder\.start([^),]\+\))/\1, {})/' XmlMaterialProfile.py

Use at your own risk, of course :grimacing:

[a123qwertz567]

Thank you for the solution. I will not try it if it works I am fine for now. The whole settings, profile, filament management is a mess from my perspective. I won't waste time to dial in setting in something that can break tomorrow....

[Ghostkeeper]

This has recently been fixed for us through a pull request: https://github.com/Ultimaker/Cura/pull/9105

The changes suggested by @c24w and applied by @lorenzph are backwards compatible to Python 3.5. So it apparently fixes it for Python 3.9, and doesn't break anything for the main Cura distribution. So we've merged them in. Thanks for the debugging, guys :)