Gazebo can't startup occasionally with 'undefined symbol: _ZN3ros13isInitializedEv' ?

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I startup the gazebo8 by roslaunch and use with my own GUI plugin. But the gazebo can't startup occasionally with the output:

gzclient: symbol lookup error: /home/xxx/catkin_ws/devel/lib/libxxxplugin.so: undefined symbol: _ZN3ros13isInitializedEv

I am sure that the plugin is loaded. What is the reason?