Page MenuHome

Error spam in console when opening file from 2.7x
Closed, ResolvedPublicBUG


System Information
Operating system: Windows 10
Graphics card: GeForce GTX 1080

Blender Version
Broken: version: 2.83 (sub 11), branch: master, commit date: 2020-04-01 17:35, hash: a9963669f9d2, type: Release, uild date: 2020-04-02, 06:54:40
Worked: 2.79b

Many of my files created in 2.7x often spam the console with the following error when opened in 2.8x:

write_customdata error: layer '':15 - can't be written to file

Where '15' can be other numbers. Sometimes dozens of times whenever whatever is throwing this error updates, such as on a frame change, and blender is momentarily unresponsive.

I've found that through process of elimination by deleting data, and I've tracked down a specific example of a mesh data block that triggers the error so you can repro. Deleting the object does not stop the error, but deleting the mesh data immediately does.

I can't stress enough that this normally applies to dozens of objects in a complex file like a rigged character, so tracking down each one is a long process during which blender is extremely laggy.

Repro steps:
Open attatched .blend file, open console, and change the current frame. Since I've only kept one piece of mesh data that causes it, you should see the error once per frame change.

Note: For some reason, switching into and out of edit mode also stops the error, but this isn't always practical in a complex file with hundreds or thousands of objects.

Event Timeline

Richard Antalik (ISS) changed the task status from Needs Triage to Confirmed.Apr 9 2020, 3:03 PM
Bastien Montagne (mont29) triaged this task as Low priority.
Bastien Montagne (mont29) changed the subtype of this task from "Report" to "Bug".

Error message in itself is valid, issue here is that it is printed out on every undo step storage.

Note that switching to Edit mode, or saving/reloading once, will clear the stale invalid data, so you would not have those errors anymore.

Will silence the error when writing undo memfile.

The other issue is that the message does not say which object(s) are causing the error, so identifying the offending object in a file with hundreds or thousands of objects is problematic.