Server crash when pregenerating chunks (1.7.10) #115
Description
Minecraft Version
1.7.10
Mod Version
[Chunk-Pregenerator-1.7.10-4.4.9.jar]
Forge Version
[forge-1.7.10-10.13.4.1614-1.7.10]
Description
When I try to pregen chunks on my server it crashes several times. I dont know a lot of how to identify a crash, so i asked AI. This is what it told me this time (as i said, it had different reasons why it crashed, but always because of mobs):
Cause of the Crash:
The key part of the error is this line:
java.lang.IllegalArgumentException: Tile entity of type net.minecraft.tileentity.TileEntityMobSpawner ...
reports coordinates of (-499, 25, -2329) that lie outside of the bounds of chunk (x=-3, z=-147)
This means the server loaded a Mob Spawner (TileEntityMobSpawner) that:
has coordinates that don’t belong to the chunk it’s being saved in,
in other words, the block “claims” to be inside a different chunk.
Minecraft expects all TileEntities (like spawners, furnaces, chests, etc.) to stay within the 16×16 block limits of their chunk.
But in this case, the spawner (of a “Rat” — most likely from Primitive Mobs or Mo’Creatures) had invalid coordinates inside the chunk’s save data.
When the Chunk Pregenerator tries to load or light that chunk during pregeneration, Forge detects that the data is corrupted and throws a fatal exception (IllegalArgumentException), which crashes the server.
Where the Error Comes From:
The key stacktrace line:
pregenerator.impl.processor.generator.ChunkProcessor.onTickEnd(ChunkProcessor.java:164)
shows that the crash happens during the final generation stage of the pregenerator, when it tries to check the chunk lighting (checkLight()).
The root cause is the invalid TileEntityMobSpawner — the pregenerator only revealed the problem, it didn’t create it.
This usually happens because of:
Dungeon mods that generate structures misaligned with chunk borders (such as Doomlike Dungeons, Roguelike Dungeons, or Recurrent Complex);
Mob spawners from older mods like Mo’Creatures, Primitive Mobs, or OreSpawn;
And since the pregenerator loads chunks very quickly, it triggers Forge’s validation system, which detects the bad coordinates.
The full crash log is attached below.
crash-2025-10-15_15.09.08-server.txt
Thanks for maintaining 1.7.10 support!