villagers spawn in walls

I found a  1.15 village & inside it, there is a villager that spawned inside a wall. In the same village, there was also a villager that spawned up inside a tree. His head was in the bottom leave block(s) of the tree that seemed to be partly inside the tree logs a block off the ground. Freed him before getting a pic. Nither villager seemed to be taking suffocation damage.