LibreOffice Calc 5.0.X users please validate your spreadsheets or templates built with older versions, before using them for any important job (engineering or accounting coming to mind).
LibreOffice Calc 5.0.X had a major refactoring of the formula calculation engine, mainly for performance reasons.
An important (unintended?) side effect is that results shown by the new Calc 5.0.X might be different from those shown by previous releases when some spreadsheet structures and functions are in use.
I met unexpected results while using named ranges, spreadsheet functions, OpenCl and generally structures that may depend on the order of calculations. I don’t know if other structures might be affected.
A few cases have already been reported as bugs; for instance:
Calculations order do not follow cell dependencies
OPENCL: VLOOKUP returns wrong data when it is used at many cells
Named Range not working as expected (hard recalc needed)
Others, as those I witnessed, might be related to the use of “undocumented” features that nevertheless worked at least up to LibreOffice 4.0.6, like the use of named ranges within spreadsheet functions like VLOOKUP.
When not rebuilding templates according to the “new” engine, my current workaround is having LibreOffice 4.0.6 (the last stable release before all this began) to check old templates before every important use.
Other workarounds might include disabling OpenCL or enabling iterations ( Options > LibreOffice Calc > Calculate > Iterations).
