[1.1.91] One of my belt lines haves 4.2 million sulphur on it

[maltsi]

I do have few mods (list at the bottom), but this issue happens even if all of them is uninstalled. Author of IR3 mod also confirmed that this indeed happens even if his mod (and others) are removed.

Issue
One of my belt lines haves 4.2 million sulphur at the end of it. Its always the last belt on that particular line, meaning that if i build it longer, the bugged belt will move too. Inserters taking sulphur from that piece will ignore limits on assemblers and they get stuck eventually trying to add more and more of it. Belt is shared with coke, but that is not unlimited or bugged in anyway. I cannot deconstruct it with bots since it contains ridiculous amount of sulphur, i can manually pick it up, but the entire map will be filled with sulphur. and building it back will bug it again. Only fix seems to be to blow it up and then build it back.

This is what happens if i manually remove it, all of that yellow is sulphur.

20231004163651_1.jpg (1.82 MiB) Viewed 1097 times

This particular line left of me is the one with a bug.

20231004163703_1.jpg (1.86 MiB) Viewed 1097 times

Possibly cause for this is that when i copied this above sulphur production line (red circle) and pasted it below (green circle), my friend got desynced and from that point forward hes getting regular desyncs when we are near this bugged belt (blue circle). Desyncs did not happen before this bug occured.

20231004193748_1.jpg (1.62 MiB) Viewed 1097 times

To Replicate
load the save i provided and mine the last belt below the player or just pick up stuff from the last belt, it will never end.


Full mod list.

Additional paste settings (fixed)
Black Rubber Belts
Cybersyn combinator
Factorio Library
Factory Planner
Factory Search
GUI Unifyer
IR 3 and all 4 asset packs
IR 3 Deep space mining
IR 3 Powered Loaders & Ingot Stacking
Logistic Request manager (continued)
Module Inserter extented
Ore manager fixed
P.U.M.P
Project Cybersyn
Rate Calculator
Recipe Book
Solar Calculator

Logs (hopefully right one)

factorio-current.log

(30.57 KiB) Downloaded 24 times

Save File

IR3 - 3 backup.zip

(24.32 MiB) Downloaded 27 times

[Rseding91]

Do you have any way to get a known good save into a broken state like this?

[maltsi]

Do you have any way to get a known good save into a broken state like this?

Unfortunately no, i tried reproducing it quite a bit by doing exactly what i did last time. But couldn't make it happen again. It must be related to desync that happened at the exact same time when i pasted the copied chemplants that makes sulphur. or maybe something else happened same time that then caused the desync to happen. probably the last one since i can see that happen if belt randomly gets 4.2m sized stack of items to appear, but then again i don't know anything about coding so its all guesses from my side.

Could have been one off thing, or like Author of the IR3 mod said "But my gut instinct is that this is a bit-flip or some other randomness." when i reported this first to him as i thought it was his mod related.

[boskid]

From what i remember there are no known code paths that would be able to insert an item stack with more than 1 item onto a transport line, and in this case there is an item stack of sulfur with count=4193829 at the right transport line. A number that is really close to a bit flip from count=1 to count=4194305 followed by 476 sulfur being taken out by the inserters.

I wont be fixing this save file. I saw no other consistency issues and you already found the belt with the sulfur item on it that has wrong item stack count. You can launch a rocket to destroy that belt so the sulfur drops on the surface ignoring the wrong item stack count, it will leave just 4 sulfur items silently destroying all 4193828 remaining sulfur of this broken item stack.