[MC-300739] Server crash when generating custom structures containing shelf blocks

The game crashes when generating custom structures containing shelf blocks from a data pack.

How to reproduce:

Download the linked data pack and install it in a new world
Execute the command /locate example:undeground_structures/sculk_lab

Linked issues

is duplicated by 1

MC-300795 shelves in generated structures cause feature placement error in the chunk Resolved

Attachments

crash-2025-08-06_02.16.16-server.txt

Data pack.zip

Comments 2

etanaratsastaja 2025-08-07T07:47:12Z

The same data pack shouldn’t work on 1.21.8 considering it contains shelf blocks

The Brook 2025-08-11T12:01:17Z

@etanaratsastaja It does work, it simply doesn’t generate the shelves. But the issue isn’t the shelves but the crash in version 25w32a. The shelves are not relevant to this issue, I was stating that this same data pack didn’t make the game crash in previous stable version.