# Crash when initializing app built and run from Ubuntu 20.04

**URL:** <https://discourse.slicer.org/t/crash-when-initializing-app-built-and-run-from-ubuntu-20-04/13265>\
**Category:** Development\
**Tags:** build\
**Created:** [August 31, 2020, 7:56pm UTC](https://discourse.slicer.org/t/crash-when-initializing-app-built-and-run-from-ubuntu-20-04/13265 "2020-08-31T19:56:57Z")\
**Posts on this page:** 1\
**Showing post:** 8

<div class="post-metadata">

**Author:** ![lassoan](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/lassoan/32/13_2.png) [@lassoan](https://discourse.slicer.org/u/lassoan)\
**Post date:** [August 31, 2020, 9:39pm UTC](https://discourse.slicer.org/t/crash-when-initializing-app-built-and-run-from-ubuntu-20-04/13265/8 "2020-08-31T21:39:25Z")

</div>

Knowing that the crash occurred in libc is not very useful. Can you get a stack trace? This may help: [https://www.slicer.org/wiki/Documentation/Nightly/Developers/Tutorials/Debug\_Instructions#Analyze\_a\_segmentation\_fault](https://www.slicer.org/wiki/Documentation/Nightly/Developers/Tutorials/Debug_Instructions#Analyze_a_segmentation_fault)

I’ve tried to start Slicer in gdb on Linux by following [these instructions](https://www.slicer.org/wiki/Documentation/Nightly/Developers/Tutorials/Debug_Instructions#GDB_debug_with_launch_arguments), I get the error below. When I try to debug using VS Code, I get the same error.

```auto
osboxes@osboxes:~/D/Slicer-SuperBuild-Release/Slicer-build$ ./Slicer --launch /usr/bin/gnome-terminal
Fatal Python error: init_import_size: Failed to import the site module
Python runtime state: initialized
Traceback (most recent call last):
  File "/home/osboxes/D/Slicer-SuperBuild-Release/python-install/lib/python3.6/site.py", line 553, in <module>
    main()
  File "/home/osboxes/D/Slicer-SuperBuild-Release/python-install/lib/python3.6/site.py", line 539, in main
    known_paths = addusersitepackages(known_paths)
  File "/home/osboxes/D/Slicer-SuperBuild-Release/python-install/lib/python3.6/site.py", line 282, in addusersitepackages
    user_site = getusersitepackages()
  File "/home/osboxes/D/Slicer-SuperBuild-Release/python-install/lib/python3.6/site.py", line 258, in getusersitepackages
    user_base = getuserbase() # this will also set USER_BASE
  File "/home/osboxes/D/Slicer-SuperBuild-Release/python-install/lib/python3.6/site.py", line 248, in getuserbase
    USER_BASE = get_config_var('userbase')
  File "/home/osboxes/D/Slicer-SuperBuild-Release/python-install/lib/python3.6/sysconfig.py", line 601, in get_config_var
    return get_config_vars().get(name)
  File "/home/osboxes/D/Slicer-SuperBuild-Release/python-install/lib/python3.6/sysconfig.py", line 550, in get_config_vars
    _init_posix(_CONFIG_VARS)
  File "/home/osboxes/D/Slicer-SuperBuild-Release/python-install/lib/python3.6/sysconfig.py", line 421, in _init_posix
    _temp = __import__ (name, globals(), locals(), ['build_time_vars'], 0)
ModuleNotFoundError: No module named '_sysconfigdata__linux_x86_64-linux-gnu'

```

@jcfr Do you know how to fix this?

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_[View the full topic](https://discourse.slicer.org/t/crash-when-initializing-app-built-and-run-from-ubuntu-20-04/13265)._