In the latest snapshot (18w16a), eyes of ender and /locate point the player towards a location where there is no stronghold. In a world with seed -4689481405078176436, I am directed towards 8, ~ -8, but there is no stronghold here or in a 1.12.2 world of the same seed. In 1.12, i am directed to -1240 ~ -808, where there is a stronghold in 1.12 only.