It is hard to troubleshoot without backtrace, maybe you still have it in the scroll buffer of the terminal.
If not, the best is you upgrade to latest 5.8.x, there were many fixes since 5.8.2 and it could be a side effect of one of them. If still happens, copy the core file to some other system from where you can get it back on the system that generated it for further analysis. The full backtrace is important, but then other data from core file might be needed for proper troubleshooting.