Tor Lillqvist (and others) have done a lot to add the Calc feature of Threaded Calculation (i.e., multi-threading / parallelism). It is now enabled by default in version 6.0+. Since this is a new feature, we expect that a lot of bugs may appear which may be related to this. This is a meta tracker for Calc Threaded Calculation bugs. More about multi-threading in Calc: LibreOffice Calc Is Finally Being Threaded https://www.phoronix.com/scan.php?page=news_item&px=LibreOffice-Calc-Threading Making Calc Calculate in Parallel https://conference.libreoffice.org/assets/Conference/Rome/Slides/libocon-2017-novideos.pdf
Bug 114157 may be the first bug I have fould to be related to Calc multi-thread calculation.