Game crashes on loading world with a java.lang.StackOverflowError after using structure blocks due to multiple block entities in the same location
I ([Mod] Pokechu22) have written a tool that can recover your world by removing the duplicated block entities:
- For safety, make a complete backup of your world (this tool modifies files in-place).
- Download this program (source code). Make sure your browser saves it as a .jar file, not a .zip file.
- Run it. A window should open.
- Select "add files", and then find your world, enter the region folder, and select the mca file with the duplicate block entity. If you don't know which file that is, just select them all.
- Wait while the tool runs. Any duplicate block entities will be output in the log (full NBT); other chunks will just have counts.
- The world should now load ingame.
If you have any further information about this bug, please comment.
I thought that using structure blocks would allow me to copy-paste buildings, and it did. However, now that I've done it, opening the map crashes the game. There was another folder created (that wasn't there before) that had a weird symbol in front of the name, and I deleted that after it started crashing.
I honestly don't know if it can be reproduced, and I just want this world back. I hadn't backed it up in a while, and it was really important to me.
Linked Issues
is duplicated by3
MC-109939What actually happened was that when I played my world it was loading well, but then it came out a report saying that the game has crashed. DuplicateMC-120459Crashes right when joining a single player world: java.lang.StackOverflowErrorDuplicateMC-123636Crashes when trying loading chunk.Duplicate
![[Mod] Pokechu22](../../../data/avatars/users/92931.png){kind=small}
Created Issue:
I used structure blocks in an important world, and now if I open it (or a copy of it) it crashes the game
I thought that using structure blocks would allow me to copy-paste buildings, and it did. However, now that I've done it, opening the map crashes the game. There was another folder created (that wasn't there before) that had a weird symbol in front of the name, and I deleted that after it started crashing.
I honestly don'y know if it can be reproduced, and I just want this world back. I hadn't backed it up in a while, and it was really important to me.
Environment
OS: Mac OS X (ver 10.9.5, arch x86_64)
Java: 1.6.0_65 (by Apple Inc.)
Launcher: Minecraft Launcher 1.6.61 (bootstrap 5)
Minecraft: 1.10.2 (updated Sat Oct 22 15:28:03 CDT 2016)
![[Mod] Neko](../../../data/avatars/users/92901.png){kind=small}
![[Bot] Arisa](../../../data/assets/gravatar/mustek2.png){kind=small}
I thought that using structure blocks would allow me to copy-paste buildings, and it did. However, now that I've done it, opening the map crashes the game. There was another folder created (that wasn't there before) that had a weird symbol in front of the name, and I deleted that after it started crashing.
I honestly don'
yknow if it can be reproduced, and I just want this world back. I hadn't backed it up in a while, and it was really important to me.I thought that using structure blocks would allow me to copy-paste buildings, and it did. However, now that I've done it, opening the map crashes the game. There was another folder created (that wasn't there before) that had a weird symbol in front of the name, and I deleted that after it started crashing.
I honestly don't know if it can be reproduced, and I just want this world back. I hadn't backed it up in a while, and it was really important to me.
I used structure blocks in an important world, and now if I open it (or a copy of it) it crashes the gameCrash with structure blocks
I also have this problem. I saved a hopper clock with a structure block and loaded it and now my world won't load. Crash report is here:https://drive.google.com/open?id=0B0hGczKpXv5TdC1SbUNBaTNZYjQ
![[Mod] Michael Wobst](../../../data/avatars/users/37868.png){kind=small}
![[Mod] violine1101](../../../data/avatars/users/92858.png){kind=small}
relates to
is duplicated by
relates to
Crash with structure blocksGame crashes on loading world with a java.lang.StackOverflowError after using structure blocks due to multiple block entities in the same location
WorkaroundI ([Mod] Pokechu22) have written a tool that can recover your world by removing the duplicated block entities:
- For safety, make a complete backup of your world (this tool modifies files in-place).
- Download this program (source code). Make sure your browser saves it as a .jar file, not a .zip file.
- Run it. A window should open.
- Select "add files", and then find your world, enter the region folder, and select the mca file with the duplicate block entity. If you don't know which file that is, just select them all.
- Wait while the tool runs. Any duplicate block entities will be output in the log (full NBT); other chunks will just have counts.
- The world should now load ingame.
If you have any further information about this bug, please comment.
I thought that using structure blocks would allow me to copy-paste buildings, and it did. However, now that I've done it, opening the map crashes the game. There was another folder created (that wasn't there before) that had a weird symbol in front of the name, and I deleted that after it started crashing.
I honestly don't know if it can be reproduced, and I just want this world back. I hadn't backed it up in a while, and it was really important to me.
WorkaroundI ([Mod] Pokechu22) have written a tool that can recover your world by removing the duplicated block entities:
- For safety, make a complete backup of your world (this tool modifies files in-place).
- Download this program (source code). Make sure your browser saves it as a .jar file, not a .zip file.
- Run it. A window should open.
- Select "add files", and then find your world, enter the region folder, and select the mca file with the duplicate block entity. If you don't know which file that is, just select them all.
- Wait while the tool runs. Any duplicate block entities will be output in the log (full NBT); other chunks will just have counts.
- The world should now load ingame.
If you have any further information about this bug, please comment.
I thought that using structure blocks would allow me to copy-paste buildings, and it did. However, now that I've done it, opening the map crashes the game. There was another folder created (that wasn't there before) that had a weird symbol in front of the name, and I deleted that after it started crashing.
I honestly don't know if it can be reproduced, and I just want this world back. I hadn't backed it up in a while, and it was really important to me.
WorkaroundI ([Mod] Pokechu22) have written a tool that can recover your world by removing the duplicated block entities:
- For safety, make a complete backup of your world (this tool modifies files in-place).
- Download this program (source code). Make sure your browser saves it as a .jar file, not a .zip file.
- Run it. A window should open.
- Select "add files", and then find your world, enter the region folder, and select the mca file with the duplicate block entity. If you don't know which file that is, just select them all.
- Wait while the tool runs. Any duplicate block entities will be output in the log (full NBT); other chunks will just have counts.
- The world should now load ingame.
If you have any further information about this bug, please comment.
I thought that using structure blocks would allow me to copy-paste buildings, and it did. However, now that I've done it, opening the map crashes the game. There was another folder created (that wasn't there before) that had a weird symbol in front of the name, and I deleted that after it started crashing.
I honestly don't know if it can be reproduced, and I just want this world back. I hadn't backed it up in a while, and it was really important to me.
Is this still an issue in the most recent versions (currently that is 1.12) of Minecraft? If so, please update the affected versions and help us keeping this ticket updated from time to time. If you are the owner/reporter of this ticket, you can modify the affected version(s) yourself.
is duplicated by
OS: Mac OS X (ver 10.9.5, arch x86_64)
Java: 1.6.0_65 (by Apple Inc.)
Launcher: Minecraft Launcher 1.6.61 (bootstrap 5)
Minecraft: 1.10.2 (updated Sat Oct 22 15:28:03 CDT 2016)
Actually, I recognize that stack trace. Were you messing around with structure blocks? If so, this is probably MC-109348 - for some reason, there's 2 block entities at the same location. There's a tool attached to that ticket that should hopefully be able to recover the world (though I wrote that a while ago and I don't remember too much about it).
Still attach the world, though, please.
Yep, this is MC-109348.
Duplicate TE at -47 68 -437!
1:
TAG_Compound: 9 entries
{
TAG_Short("CookTime"): 0
TAG_Int("x"): -47
TAG_Short("BurnTime"): 0
TAG_Int("y"): 68
TAG_Int("z"): -437
TAG_List("Items"): 0 entries of type TAG_End
{
}
TAG_String("id"): minecraft:furnace
TAG_Short("CookTimeTotal"): 0
TAG_String("Lock"):
}
2:
TAG_Compound: 9 entries
{
TAG_Short("CookTime"): 0
TAG_Int("x"): -47
TAG_Short("BurnTime"): 0
TAG_Int("y"): 68
TAG_Int("z"): -437
TAG_List("Items"): 0 entries of type TAG_End
{
}
TAG_String("id"): minecraft:furnace
TAG_Short("CookTimeTotal"): 0
TAG_String("Lock"):
}
Duplicate TE at -47 72 -433!
1:
TAG_Compound: 8 entries
{
TAG_Int("Secondary"): 0
TAG_Int("Primary"): 0
TAG_Int("x"): -47
TAG_Int("y"): 72
TAG_Int("Levels"): 0
TAG_Int("z"): -433
TAG_String("id"): minecraft:beacon
TAG_String("Lock"):
}
2:
TAG_Compound: 8 entries
{
TAG_Int("Secondary"): 0
TAG_Int("Primary"): 0
TAG_Int("x"): -47
TAG_Int("y"): 72
TAG_Int("Levels"): 0
TAG_Int("z"): -433
TAG_String("id"): minecraft:beacon
TAG_String("Lock"):
}
Rewriting section!
REGION SAVE r.-1.-1.mca[29,4] 3783B = rewrite 171
--- 29, 5: 16 tile entities ---
Duplicate TE at -47 73 -428!
1:
TAG_Compound: 6 entries
{
TAG_Int("x"): -47
TAG_Int("y"): 73
TAG_Int("z"): -428
TAG_List("Items"): 0 entries of type TAG_End
{
}
TAG_String("id"): minecraft:chest
TAG_String("Lock"):
}
2:
TAG_Compound: 6 entries
{
TAG_Int("x"): -47
TAG_Int("y"): 73
TAG_Int("z"): -428
TAG_List("Items"): 0 entries of type TAG_End
{
}
TAG_String("id"): minecraft:chest
TAG_String("Lock"):
}
Duplicate TE at -47 73 -426!
1:
TAG_Compound: 6 entries
{
TAG_Int("x"): -47
TAG_Int("y"): 73
TAG_Int("z"): -426
TAG_List("Items"): 0 entries of type TAG_End
{
}
TAG_String("id"): minecraft:chest
TAG_String("Lock"):
}
2:
TAG_Compound: 6 entries
{
TAG_Int("x"): -47
TAG_Int("y"): 73
TAG_Int("z"): -426
TAG_List("Items"): 0 entries of type TAG_End
{
}
TAG_String("id"): minecraft:chest
TAG_String("Lock"):
}
I still don't know why this happened in the first place, though, other than that structure blocks are involved. You attached your structures, so that should help.
I've attached r.-1.-1.fixed.mca
. Replace region/r.-1.-1.mca with it and everything should load fine.
Please make sure that you're using either official Linux launcher (the java-based one or the staging ones available as arch and deb packages (there may be a newer non-staging link, but I don't use Linux so I'm not sure how to find it)). Please also note that launching a world from a newer version in an older version may corrupt the world, so avoid doing that.
In any case, this issue looks like MC-109348. I can walk you through the steps for repairing your world, if you need help (make a full backup first).
I had 2 hoglins in my game and we decided to bring them into the overworld and put them in a fenced area. We named them, and put warped fungus around to scare them. This kept them running in big circles forever. Once we took away the fungus, They always were either going almost inside of each other, or running in the direction of any player. While running into the direction of any player, or bumping into each other constantly, it caused a big problem. Them being near or inside of each other crashed the game. This made it so every time I attempted to join the server, it crashed. I fixed it by having my friend kill them by shooting arrows down onto the spot where the hogs were barely visible, until one died. The crash error was: java.lang.StackOverflowError.
This crash I researched and found associated with blocks being stuck in each other. A simular issue i found recorded, MC-109348 , stated this exact problem, but in an older version of the game. I hope you can test and find this bug, and fix it immedietly for future snapshots and the final version of this update.
Please attach the crash report (.minecraft/crash-reports/crash-<DATE>-client.txt) here.
Your Java is heavily outdated. You can find the latest version here. Does this issue still occur after updating to the latest version?
Will this update fix my world or is it permanently corrupted?
Could you please attach your world (zipped) and the structure file?
I can't. It's over 600 mb and the limit here is 10
Cannot reproduce the crash by loading any of the structure files attached.
Please upload the world to a file sharing site, and share the link.
I'll see what I can do. I updated my Java and my computer as a whole, and the issue is still there. I just want this world back. If it means undoing the structures, that's fine.
I've done everything you've suggested, and I still can't open the world. I've updated Java, I downloaded the better launcher, I updated my entire OS, and yet it still won't open. I'm uploading it to mediafire, I will put a link here when it is uploaded.
Here's a mediafire version of the map. I hope it helps.
http://www.mediafire.com/file/llnggas685x38ka/The_Syndicate_Epic_Seed_%21_-_Copy.zip
Oh, hey, I recognize this crash! Same thing happened with a mod that I developed (same infinite recursion with chests looking for their neighbors). I'm not sure how you managed to break your world like that, but it is corrupted right now.
I'm pretty sure this is fixable; I'll try and repair it. I'd love to know how you managed that with structure blocks though; this kind of crash is hard to get.
I'll try to fix it. Plugging your coordinates (found under "Player Count" in the crash report) to dinnerbone's coordinate tools, the corrupted section is somewhere in r.0.0.mca. Interestingly, there is an old version of that named r.0.0.mcr, last modified 2012 - probably not a backup you want to restore.
Unfortunately, that crash report doesn't give the block that caused it. But I can look for all tile entities in the world and search for some with the same coordinates. And among the other things I found (a sign that says "We Are Watching You!" at 199, 67, 211 is probably the most interesting), most of the tile entities in the chunk at (26, 2) have a duplicate at the same coordinates. Those are causing the crash.
So I wrote a second program that simply finds duplicate tile entities and purges them. Luckily, Mojang publicly released a utility that converts region files, but it's also highly convenient work working with them in other ways (including one of the nicest NBT implementations I've ever used). That program fixed all of the duplicate tile entities in that chunk, pretty quickly. I've attached both the program (RepairTool.zip
) and the fixed r.0.0.mca to this ticket - download r.0.0.mca
and overwrite the one currently in your world's region folder and the world should stop crashing.
I'd still love to know how you managed to get these duplicate tile entities in the first place; structure blocks shouldn't do that. Assuming that this happened without mods, there is still a bug here that needs to be fixed that corrupts worlds. Your world should hopefully be fine for the future, but we need to figure out what caused this to happen in the first place.
@[Mod] Pokechu22 - Thank you! I was watching this ticket as I have had a world I had spent months working on get corrupted (MCPE) and could not recover. I switched to the PC version as I could and do frequently back up worlds. I am now working a lot with structure blocks and this ticket you could say really was going to put damper on it. The knowledge these tools by Mojang devs (I don't like using mods) could help me recover a world is invaluable until the bug is identified and fixed.
Thank you so much! This did the trick, and now I have my world back. I think I know how I caused the crash. The structures I used were all part of the same ship, and I accidentally made it so that they overlapped on a single layer. This meant that when I used the two structures, they ended up both putting blocks in the exact same place.
Again, thanks for the help. I never would've figured this out on my own, and thanks to you, I have my most important world back. I promise to be more careful with structure blocks in the future.
@jag That crash report is for modded 1.7.10; we don't support older versions and modded versions on this tracker (and IIRC 1.7.10 doesn't have structure blocks either), and even then doesn't seem to be related to this specific issue (from the crash) - this is related to malformed NBT data; that's somewhere in the rendering process. Contact the Galacticraft developer; they'll probably be able to help.
If you attached the wrong crash report, that's fine, just get the right one and I'll take a quick look and see if it's this issue or another one.
We've figured out the basic steps to trigger this.
Notes
First off, it's important to note that the duplicate block entities were in the area that was being saved by a structure block - not the loading area (as I initially thought). This can be seen on the world from this ticket ("The Syndicate Epic Seed ! - Copy") - there are still structure blocks left over for saving, and the locations of the duplicate block entities are within there.
Secondly, it was initially noticed that all of the duplicate block entities were in the same chunk, but across multiple structure blocks (and there was one block entity that wasn't duplicated, which was part of a double-chest that stretched across chunk borders at 426 81 47). However, this observation seems to be less important, as the city world from the other ticket had duplicated ones in multiple chunks, and there were a lot of block entities that weren't duplicated (including parts of a double chest). So as far as we can tell, this is a red herring.
Cause of corruption + steps to reproduce
The key observation came from [Mod] NeunEinser: Chunk.getTileEntity(BlockPos, EnumCreateEntityType) can create a new block entity when IMMEDIATE is used. And, IMMEDIATE is used when World.getTileEntity(BlockPos) is called. However, this itself doesn't immediately seem like a problem - after all, it's definitely intended that it creates a new block entity.
Yet it is. Grab the attached test world
(extract into a new folder), which contains a chest in the 0, 0 chunk that was NBTEdited to not have a block entity (more on this later) and a structure block that saves that chest. Open the structure block, and save it. Then save it a second time. Exit and reload the world; you will get this crash (and NBTEditing again shows that there are two chest block entities in the same location).
Why does this happen? It seems like it should be impossible to have two block entities in the same location, as chunks use Map<BlockPos, TileEntity> tileEntities which must have unique keys; it seems impossible for it to initially get into this state.
However, that assumption is false. If a MutableBlockPos is used, it can be put into that map, and then change position, which causes the behavior of the map to be unspecified (but in this case just means that it won't overwrite or get the MutableBlockPos-keyed block entity). Does this ever happen in practice? Yes!
The way that structure blocks save involves a loop that looks like this (simplified):
Now, if there already is a block entity in that location, then getTileEntity will work fine. But if it ends up creating one, that passes the MutableBlockPos to Chunk.addTileEntity(BlockPos, TileEntity), which puts the MutableBlockPos as a key in the tileEntities map (and tells the block entity that it is located at that position via TileEntity.setPos, which makes an immutable copy). Then afterwards, the MutableBlockPos changes, so the block entity is "lost". Saving again adds it the second time (because since the MutableBlockPos changed, the map doesn't return it when checking for existing block entities).
But, when the world is saved, it uses chunk.getTileEntityMap().values(), which will include both block entities keyed by MutableBlockPos instances. And, since the location was captured immutably before, these will both actually save the correct location values (and not the ones wherever the MutableBlockPos ended up). Thus, multiple block entities are saved at the same location.
I've identified a second location where this can also be an issue: /testforblocks also uses a loop with MutableBlockPos that calls getTileEntity. It's a little more complicated to reproduce this bug that way, though, so I won't explain the details; just note that this technichally isn't a bug with structure blocks.
Fix for corruption
Simply put, avoid calling setTileEntity or addTileEntity with a MutableBlockPos. I'd do that by changing this:
to this:
(note that the QUEUED mode does not appear to be used currently, but would still have problems if a MutableBlockPos were used).
For similar reasons, the call to setTileEntity in Chunk.setBlockState should also call toImmutable (however, I don't know of any current situation where setBlockState is called with a MutableBlockPos):
this.world.setTileEntity(pos.toImmutable(), tileentity1);Cause of crash
All of the above explains how two block entities got put in the same location. But it doesn't explain why that causes a crash. Well, first off, here's a snippet of the crash report with MCP names (with 3 lines repeated):
This is fairly easy to understand: Chunk.addTileEntity contains this code:
TileEntityChest.invalidate looks like this:
checkForAdjacentChests calls getAdjacentChest for the 4 cardinal directions. getAdjacentChest first calls isChestAt, and then does some checking on the block entity if there is a chest there. Here's isChestAt:
Since the chunk has not been (fully) loaded, calling getBlockState will attempt to load it again. Which repeats the whole process once it attempts to add the second chest block entity, forever, until the stack overflows and the game dies.
Fix for already corrupted worlds
There's two ways of fixing already corrupted worlds: fixing the chest case, or detecting and rejecting duplicate block entities when chunks are loaded. I'd favor the later one.
The chest case
Here's a possible way to handle the chest case: if the world hasn't loaded the chunk containing the block entity yet, don't check for adjacent chests. This requires adding a public method to check if a chunk is loaded.
The general solution
Here's a more general solution to the problem that rejects all duplicate block entities. The original code to read block entities is this:
Checking for duplicate block entities could be done like this:
I include both the new and the original NBT in the log just because I'm paranoid about dropping data without any way to recover it, which makes complicates this slightly; if it seems like that's unnecessary, then this can be simplified to just use a HashSet.
But how does this situation occur without NBT editing?
I don't know. I still haven't figured out how a block which should have a block entity can be created without the block entity.
One idea (from [Mod] NeunEinser) was that it could happen when downgrading from 1.11 to 1.10; while this is definitely a possibility, it seems unlikely (this ticket was created early on in the 1.11 snapshots, and there doesn't seem to be any indication that the world was loaded in them; another reproduction happened in 1.12 and it seems unlikely that they downgraded to 1.10 and then loaded in 1.12 again).
Another possibility is that the block was first set with a call to setBlockState using a MutableBlockPos, which would also create a block entity using one. However, I cannot find any evidence of this being the case. But, if this hypothetical situation did occur, then the same problem would happen.
It seems like there must be a way this could happen, but it's still unknown.
Is this still a issue in the latest version of the game(currently 1.13.1)?
If so, please add it to the affected versions, thanks!
The crash was fixed in 17w47a (the flattening) since chests now store their connections directly in the block state and they aren't determined by the block entity. I'm still trying to figure out whether the duplicate block entity situation can still be triggered – it seems like it should still be possible but I'm having trouble with it. I'll probably create a separate ticket for that behavior if it still exists.
The duplicate block entity thing doesn't seem to be happening anymore, but I'm not entirely sure from when (it happens in 18w06a, but in 18w15a it doesn't happen and no TE is saved but one is saved in the structure, and in 18w47b only one is saved somehow). As far as I can tell mutable positions are still used, though it might be the case that that was just fixed in a different version and I haven't searched well enough. Since it seems to be fixed, I'm not going to create a separate issue for it.
The crash was definitely fixed in 17w74a though.