Webots crash on save

[PhilDel32]

Describe the Bug
Webots crashes every time I click on 'save' button.

Steps to Reproduce

1. Install webots with APT or from the tarball package.
2. Launch webots from a terminal.
3. Create a new world (the same as in webots documentation, Tutorial 1, Hands-on 1 and 2)
4. Click on 'Save'
5. The .wbt file is saved but webots crashes with the following output :
   corrupted double-linked list
   /usr/local/bin/webots : ligne 105 : 3936 Abandon (core dumped)"

Expected behavior
The .wbt file saved without crashing.

Screenshots
If applicable, add screenshots to help explain your problem.

System

• Operating System: LMDE 6
• Graphics Card: NVIDIA GeForce RTX 4070
  Additional context
  The LMDE 6 install is new, the same for webots (R2023b).
  It also crashes if I add a "RectangleArena" nodes or I reuse an existing example (after copying it in a directory with write permissions)

[Flamisell]

Hi Phil,

did you solve this? I have the same problem.

[PhilDel32]

Hi,
No, I simply created a dual boot with Ubuntu 22.04 just for Webots and everything works fine on this configuration.

[ShuffleWire]

I don't have idea why it could fail here. I don't know if you are familiar with the process, but it would be great if you could build Webots in debug mode, and see what gdb say about that !
If you are willing to do that but don't know how, I could guide you :) Otherwise, that not a big deal if you don't want to investigate, as Webots is first developed for Ubuntu in mind

[PhilDel32]

Hi,
I created a new machine with LMDE 6, installed all the tools required, downloaded the sources, compiled it and guess what : No crash on saving with this executable :-)
Philippe.

[ShuffleWire]

Did you checkout the branch/tag 2023b before compiling ?

[PhilDel32]

it is the R2023b revision 1 version (April 29, 2024 source code)

[omichel]

Do you also get no crash from the nightly builds?

[Flamisell]

I am having the same Issue with nightly builds (2023b).

[PhilDel32]

Ok, I do not test the nightly build, except if it worth trying to compile this source code but it is a 3 week ago source code according to the zip file (April 29, 2024 nightly build).

[ShuffleWire]

Ok, for those how can test on this specific system (@PhilDel32 on your LMDE), I could give help. I don't know your expertise with that, so don't be shy to ask for precision, but don't be bothered by me taking your hand :)
The process will allows us to see what line is causing you a crash. It could be a memory error, or an false assertion for instance. The traceback will show us where is the program at just before dying !

1. Checkout on whatever version you experience the crash
2. Build webots in debug mode make debug
3. Run webots, and check if the crash still occurs.
   If no, then say me.
   Else, then...
4. Restart webots, and leave it untouched
5. Get it's PID : on my machine, the easiest way is to use pidof webots-bin, but on your distribution it might be different
6. Attach gdb to webots : gdb -p pid_of_the_process
7. Type continue, and check if webots is still alive. (could you interact with it normally ?)
8. Try to reproduce the crash in webots
   If it don't happen (webots do the operation happily) then say me.
   If it happen (webots should freeze), then...
9. In gdb terminal, type where, and copy paste here the log it show you. Please ensure you get all the traceback, it could be very long, like 100 lines long.

[PhilDel32]

Yes, I could do that but if I build webot from source on my LMDE machine, it does not crash when I save. I may have 2 options :

• Rebuild in debug mode on an Ubuntu 22.04 and copy the library and the executable on my LMDE machine and do the test like you suggest above.
• Get a version you compile for Ubuntu in debug mode and do the test on my LMDE machine. I guess this is a better option, we will avoid side effects we could have if I compile by myself.

[ShuffleWire]

Whelp... webots-bin is 171MB, so not gonna fit here xD

Just for me : where did you get the buggy version you run on your LMDE ?

[ShuffleWire]

@Flamisell are you on LMDE as well ?

[PhilDel32]

I got it by running the Debian installation procedure :

sudo mkdir -p /etc/apt/keyrings
cd /etc/apt/keyrings
sudo wget -q https://cyberbotics.com/Cyberbotics.asc
echo "deb [arch=amd64 signed-by=/etc/apt/keyrings/Cyberbotics.asc] https://cyberbotics.com/debian binary-amd64/" | sudo tee /etc/apt/sources.list.d/Cyberbotics.list
sudo apt update
sudo apt install webots

[ShuffleWire]

Ok then... If the version you build yourself work just fine, by all mean, that could be the solution.
Maybe running software made for Ubuntu in LMDE triggers so bad behavior, some library could be faulty, idk.

I know that Cyberbotics don't "support" others distribution than Ubuntu, so I could understand they don't want to bother with that.

[Flamisell]

Nope :/

NAME="Ubuntu"
VERSION="20.04.6 LTS (Focal Fossa)"

should I install the 2024 version?

[ShuffleWire]

Nope :/

NAME="Ubuntu" VERSION="20.04.6 LTS (Focal Fossa)"

should I install the 2024 version?

I don't think it will change the issue, but you can try

Are you able to manually build Webots from source ? If so, it would be handy if you could rebuild from source, and run the debugger on it.