Segmentation Fault when quitting simulation examples using ESCAPE key on MjViewer

[silicondosa]

Describe the bug I get a segmentation fault upon quitting any MjViewer with the ESCAPE key. This doesn't break the simulation itself - but I was concerned nevertheless.

To Reproduce On a fresh Ubuntu 20.04 installation with MuJoCo, run the following commands:

• libgl1-mesa-dev libgl1-mesa-glx libglew-dev libosmesa6-dev software-properties-common net-tools virtualenv xpra xserver-xorg-dev patchelf
• export LD_PRELOAD=/usr/lib/x86_64-linux-gnu/libGLEW.so${LD_PRELOAD:+:${LD_PRELOAD}}
  • If I didn't do this, I get the error described in #75 (I got the fix here: https://github.com/openai/mujoco-py/pull/145#issuecomment-370778622).
• pip install mujoco-py
• wget -O ~/Downloads/body_interaction.py 'https://raw.githubusercontent.com/openai/mujoco-py/master/examples/body_interaction.py'
• python3 ~/Downloads/body_interaction.py

Expected behavior The simulator will run with no errors. If you close the simulator using the ESC key, it creates a segmentation fault. However, if you close the simulator without throwing the segmentation fault.

Error Messages

Creating window glfw
Pressed ESC
Quitting.
Segmentation fault (core dumped)

Desktop (please complete the following information):

• OS: [Ubuntu 20.04]
• Python Version [3.8.5]
• Mujoco Version [mujoco 2]
• mujoco-py version [2.0.2.13]

Environment

• output of: echo $LD_LIBRARY_PATH: /home/suraj/.mujoco/mujoco200/bin
• output of: echo $HOME: /home/suraj
• output of: echo $USER: suraj