Info: Android calendar won't show repeated events (like birthdays from contacts) with a starting date before 1902

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#1

Always wondered why my Android calendar on CyanogenMod13 (Android 6.0) doesn't show up some birthday events from a few but not all contacts. After debugging i noticed that i've set a Birthday of 1900 for Contacts where i don't know the birth year.

As the Birthday evens where showing up in Thunderbird as well as in the oC internal calendar i posted a bug at the DAVdroid forums:

https://forums.bitfire.at/topic/1227/recurring-events-before-year-1902-are-not-shown-in-calendar

The thread led to an issue in 32bit integers on such 32bit devices like my smartphone. @davdroid did a really great debugging and reported that issue to the Android bugtracker:

https://code.google.com/p/android/issues/detail?id=225154

If you're affected by the same issue the workaround is for now to set a birthday year to e.g. 1902 / 2000 or similar.