Excel incorrectly assumes that the year 1900 is a leap year(learn.microsoft.com)
50 pointsby susam2 hours ago5 comments
  • nippoo2 hours ago
    In other "incorrect calendars" bugs, there's the Rockchip RK808 RTC, where the engineers thought that November had 31 days, needing a Linux kernel patch to this day that translates between Gregorian and Rockchip calendars (which are gradually diverging over time).

    Also one of my favourite kernel patch messages: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/lin....

    • tom_alexanderan hour ago
      My favorite: For one day all the Microsoft Zunes froze for the entire day, only to recover on their own 24 hours later when the infinite loop in their leap year code had finally resolved: https://web.archive.org/web/20090313105752/http://www.zunebo...
    • gerdesj2 hours ago
      To be fair, that's nowhere near as daft as september, october, november, december. Latin for seven, eight, nine, and ten is: septem, octem, novem, decem. Those are the nineth, 10th, 11th and 12th months.

      Edit: Whoops, correct eng -> latin nums

      • caminante5 minutes ago
        No? How is it octem and not octo? Does the flat bar accent do something?

        >The Latin word for "eight" is octō. [0]

        [0] asked google

      • emmelaich2 hours ago
        You may know this but originally they were 'correct' because the start of the year was March.
        • teraflopan hour ago
          Which wouldn't be that weird, except that the earliest Roman calendar started in March and ended in December, having only 10 months!

          The Romans were of course well aware that this left a gap of about two months between the end of one year in December, and the beginning of the next year in March. But they just didn't bother counting this period as part of the calendar year. Presumably because there was no agricultural reason to need accurate dates during winter.

          • shaknaa few seconds ago
            [delayed]
  • scrlk2 hours ago
    An interesting read related to this bug from Joel Spolsky - My First BillG Review: https://www.joelonsoftware.com/2006/06/16/my-first-billg-rev...
  • darknavi2 hours ago
    > Applies to: Microsoft Excel for Mac 2011, Excel for Microsoft 365 for Mac, Microsoft Office Excel 2003, Microsoft Office Excel 2007, Excel 2010, Excel 2013, Excel 2016
    • etothepii2 hours ago
      This will never stop as it would require either the reference date to be changed or fir all dates in all saved spreadsheets to be off by one.
      • gpm26 minutes ago
        Or... A version number that tells excel which convention to use?

        I suppose that would make copy and pasting formulas between spreadsheets very mildly error prone though, so it probably won't happen.

    • parenthesisan hour ago
      What about Microsoft 366?
      • a012an hour ago
        Although it is technically possible to correct this behavior so that current versions of Microsoft Copilot 366 is a leap year, the disadvantages of doing so outweigh the advantages.
  • 2 hours ago
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  • shablulman2 hours ago
    [dead]