He was buried and then died? Wow. That's tricky. Especially since we're talking about Da Vinci here, and he supposedly died in the arms of the King! (http://en.wikipedia.org/wiki/Leonardo_da_Vinci#Old_age.2C_1513-1519)
Especially when you take into account this statement from later in the article: "The church in which Leonardo was buried was destroyed after the French revolution of 1789. The remains were reburied in the castle’s smaller chapel of Saint-Hubert in 1874, beneath an inscription that describes them as “presumed” to be the master’s."