Minecraft could not calculate distance from the player to destination using the /locate command.
In the picture, my location was XYZ: 993791 / 56 / 3008381.
I used /locate command and located the nearest stronghold being at XYZ: 11768 / ~ / 19928
However, the game calculated that the player is 0 blocks away from the stronghold, which is incorrect.
This is the only structure to be calculated inaccurately, other structures (igloo, mineshaft, mansion, etc) gave correct measures.
The reason for why this only affects strongholds is probably because there are no strongholds outside of the center of the world.