Error stopping Qt's application after running for a long time

If you run the Qt5 Gui application for a long time (30 minutes, 2 hours, etc.) on Windows 10, an error such as "Application has stopped working" will occur.
A program is a program that serializes with Arduino to receive data and depicts it in a class inherited by QPainter.

If you look at the error, it seems that the array is accessing out of range, but I don't think it's happening (at least superficially).After investigating various causes, we thought that dll was insufficient and that it was because we used an executable compiled in Debug mode.
Even if you use a PC that does not have other Qt's in it, it stops irregularly even if you use the one built in release mode.
Is serial communication a problem?I'm not sure.
If you are familiar with it, please help me.Thank you.

qt qt5

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