This issue is tangentially related to #166465, but it seemed different enough to warrant a seperate issue.

GtkCalendar's UI allows for negative years to be entered by repeatedly mashing the left arrow until the year becomes < 0.

Theoretical time/space issues aside, this becomes pretty ugly when you call gtk_calendar_get_date(uint, uint, uint) as the year is returned as a uint, causing it to wrap around, and returning a nasty year like 4294967281.  Either GtkCalendar should desensitize the left arrow when the year becomes 0 (best), or return the year as a signed integer (passable).