The bug

I was locating a structure and it is for example, a million blocks away. So, I was about 2977739 blocks away, however, the game said it is about 46000 blocks away. But I came one more block away from it, it said it is 0 blocks away. This firstly happens when the distance from the closest structure exceeds 46340 blocks.

How to reproduce

1. Start a new world using the seed that is in the screenshot
2. Teleport to something like 58000 ~ 6248
3. Locate a Stronghold
   → It should be about maximally 37000 blocks away, the counting works correctly
4. Teleport 46340 blocks away from the nearest stronghold
   → Still works correctly
5. Go one more block away from it
   → It says it is 0 blocks away

Plus, it doesn't always say it is 0 blocks away. Try teleporting different distances and if you are lucky, it might not say it is 0 blocks away. Look in the screenshots.