python遇到Segmentation fault (core dumped)调试方法

python3执行某一个程序时，报Segmentation fault (core dumped)错，但没有告知到底哪里出错，无法查问题

同时在根目录下生成core文件，典型的可以用gdb进行调试。这里用另外一个方法调试。

在主程序最开始加入两行代码：

import faulthandler
faulthandler.enable()
# 下面是原代码

再执行主程序，发现输出的信息很多：

igs@igs:~/eval_viewer $ python3 main.py 
Fatal Python error: Segmentation fault

Current thread 0x00007f611cb7e740 (most recent call first):
  File "/usr/lib/python3/dist-packages/gi/_option.py", line 47 in <module>
  File "<frozen importlib._bootstrap>", line 219 in _call_with_frames_removed
  File "<frozen importlib._bootstrap_external>", line 678 in exec_module
  File "<frozen importlib._bootstrap>", line 665 in _load_unlocked
  File "<frozen importlib._bootstrap>", line 955 in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 971 in _find_and_load
  File "<frozen importlib._bootstrap>", line 219 in _call_with_frames_removed
  File "<frozen importlib._bootstrap>", line 1023 in _handle_fromlist
  File "/usr/lib/python3/dist-packages/gi/overrides/GLib.py", line 37 in <module>
  File "<frozen importlib._bootstrap>", line 219 in _call_with_frames_removed
  File "<frozen importlib._bootstrap_external>", line 678 in exec_module
  File "<frozen importlib._bootstrap>", line 665 in _load_unlocked
  File "<frozen importlib._bootstrap>", line 955 in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 971 in _find_and_load
  File "<frozen importlib._bootstrap>", line 994 in _gcd_import
  File "/usr/lib/python3.6/importlib/__init__.py", line 126 in import_module
  File "/usr/lib/python3/dist-packages/gi/overrides/__init__.py", line 125 in load_overrides
  File "/usr/lib/python3/dist-packages/gi/importer.py", line 146 in load_module
  File "<frozen importlib._bootstrap>", line 626 in _load_backward_compatible
  File "<frozen importlib._bootstrap>", line 656 in _load_unlocked
  File "<frozen importlib._bootstrap>", line 955 in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 971 in _find_and_load
  File "<frozen importlib._bootstrap>", line 994 in _gcd_import
  File "/usr/lib/python3.6/importlib/__init__.py", line 126 in import_module
  File "/usr/lib/python3/dist-packages/gi/importer.py", line 145 in load_module
  File "<frozen importlib._bootstrap>", line 626 in _load_backward_compatible
  File "<frozen importlib._bootstrap>", line 656 in _load_unlocked
  File "<frozen importlib._bootstrap>", line 955 in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 971 in _find_and_load
  File "<frozen importlib._bootstrap>", line 994 in _gcd_import
  File "/usr/lib/python3.6/importlib/__init__.py", line 126 in import_module
  File "/usr/lib/python3/dist-packages/gi/importer.py", line 145 in load_module
  File "<frozen importlib._bootstrap>", line 626 in _load_backward_compatible
  File "<frozen importlib._bootstrap>", line 656 in _load_unlocked
  File "<frozen importlib._bootstrap>", line 955 in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 971 in _find_and_load
  File "<frozen importlib._bootstrap>", line 219 in _call_with_frames_removed
  File "<frozen importlib._bootstrap>", line 1023 in _handle_fromlist
  File "/home/igs/.local/lib/python3.6/site-packages/matplotlib/backends/backend_gtk3.py", line 30 in <module>
  File "<frozen importlib._bootstrap>", line 219 in _call_with_frames_removed
  File "<frozen importlib._bootstrap_external>", line 678 in exec_module
  File "<frozen importlib._bootstrap>", line 665 in _load_unlocked
  File "<frozen importlib._bootstrap>", line 955 in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 971 in _find_and_load
  File "<frozen importlib._bootstrap>", line 219 in _call_with_frames_removed
  File "<frozen importlib._bootstrap>", line 1023 in _handle_fromlist
  File "/home/igs/.local/lib/python3.6/site-packages/matplotlib/backends/backend_gtk3agg.py", line 8 in <module>
  File "<frozen importlib._bootstrap>", line 219 in _call_with_frames_removed
  File "<frozen importlib._bootstrap_external>", line 678 in exec_module
  File "<frozen importlib._bootstrap>", line 665 in _load_unlocked
  File "<frozen importlib._bootstrap>", line 955 in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 971 in _find_and_load
  File "<frozen importlib._bootstrap>", line 994 in _gcd_import
  File "/usr/lib/python3.6/importlib/__init__.py", line 126 in import_module
  File "/home/igs/.local/lib/python3.6/site-packages/matplotlib/pyplot.py", line 277 in backend_mod
  File "/home/igs/.local/lib/python3.6/site-packages/matplotlib/pyplot.py", line 276 in switch_backend
  File "/home/igs/.local/lib/python3.6/site-packages/matplotlib/pyplot.py", line 256 in switch_backend
  File "/home/igs/.local/lib/python3.6/site-packages/matplotlib/__init__.py", line 703 in __getitem__
  File "/home/igs/.local/lib/python3.6/site-packages/matplotlib/pyplot.py", line 2336 in <module>
  File "<frozen importlib._bootstrap>", line 219 in _call_with_frames_removed
  File "<frozen importlib._bootstrap_external>", line 678 in exec_module
  File "<frozen importlib._bootstrap>", line 665 in _load_unlocked
  File "<frozen importlib._bootstrap>", line 955 in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 971 in _find_and_load
  File "<frozen importlib._bootstrap>", line 219 in _call_with_frames_removed
  File "<frozen importlib._bootstrap>", line 1023 in _handle_fromlist
  File "/home/igs/eval_viewer/eval_viewer/plot_panel.py", line 10 in <module>
  File "<frozen importlib._bootstrap>", line 219 in _call_with_frames_removed
  File "<frozen importlib._bootstrap_external>", line 678 in exec_module
  File "<frozen importlib._bootstrap>", line 665 in _load_unlocked
  File "<frozen importlib._bootstrap>", line 955 in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 971 in _find_and_load
  File "/home/igs/eval_viewer/eval_viewer/data_load_form.py", line 13 in <module>
  File "<frozen importlib._bootstrap>", line 219 in _call_with_frames_removed
  File "<frozen importlib._bootstrap_external>", line 678 in exec_module
  File "<frozen importlib._bootstrap>", line 665 in _load_unlocked
  File "<frozen importlib._bootstrap>", line 955 in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 971 in _find_and_load
  File "/home/igs/eval_viewer/eval_viewer/main_forms.py", line 9 in <module>
  File "<frozen importlib._bootstrap>", line 219 in _call_with_frames_removed
  File "<frozen importlib._bootstrap_external>", line 678 in exec_module
  File "<frozen importlib._bootstrap>", line 665 in _load_unlocked
  File "<frozen importlib._bootstrap>", line 955 in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 971 in _find_and_load
  File "main.py", line 14 in <module>
Segmentation fault (core dumped)
igs@igs:~/eval_viewer $ 

从下往上看，main.py的line 14的内容为from eval_viewer.main_forms import MainWindow，即调用了main_forms.py，该文件为自己写的
然后main_forms.py的line 9的内容为from eval_viewer.data_load_form import DataLoadForm，即调用了data_load_form.py，该文件为自己写的
然后data_load_form.py的line13的内容为from eval_viewer.plot_panel import PlotPanel，即调用了plot_panel.py，该文件为自己写的
然后plot_panel.py的line10的内容为from matplotlib import pyplot as plt，即调用了matplotlib，该文件为安装的包。

进一步验证是不是matplotlib安装的问题。

果然是该包安装有问题，百度之即可。最终解决方法：
将原代码的

from matplotlib import pyplot as plt

修改为

import matplotlib as mpl
mpl.use('Agg')
import matplotlib.pyplot as plt
复制

成功解决！