Version info

Look i use this weird version i get from leijurv that i then surgically put into impact so i dont know
1.12 Forge with a shit load of other mods but none matter for this report

How to reproduce

Have buildrepeat on a positive vertical vector
Select an area
Cleararea
(let it clear the area until all above you is void)
Crash

Modified settings

buildRepeat 0,8,0

Final checklist

• I know how to properly use check boxes
• I have included the version of Minecraft I'm running, baritone's version and forge mods (if used).
• I have included logs, exceptions and / or steps to reproduce the issue.
• I have not used any OwO's or UwU's in this issue.

1. You are using a custom build, so either you can reproduce this with an official release or this issue is invalid and you need to report it to whoever made the build, if at all
2. Mods sometimes do stuff which has no obviously visible connection to their features, so try reproducing this without them.

i mean it makes sense to me, there's no check to stop buildrepeat at build limit lmao

Build repeat doesn't stop, yes. But to me buildRepeat taking up the whole heap doesn't make sense unless the game is about to crash anyway and the builder just takes the little rest that was missing for the crash.
Since I assume the custom build was forked before #2481 I tested from 4132d6f (directly before #2481) as well as 4bc179b (newest).
On 4132d6f build repeating upwards with sel ca simply crashed with a stack overflow (no increase in memory) and
on 4bc179b my framerate dropped to 1 fps but it did neither crash nor increase memory consumption by more than 40MB (which were not freed after cancelling and manually triggering a garbage collection run, so I assume they were used by something else)

It hasn't been fixed, that is why this issue is still open.

I think the comment is there to show me that it is not a problem with the modpack (although I'm interested if it happens without impact).
Is there some place to get the obfuscation mappings from so I can deobfuscate the crash report?

Ok i did it again on 1.16.5 clean impact baritone client and a newly generated world and got the same result
label=nightly-20210308-1.16.5

Is there some place to get the obfuscation mappings from so I can deobfuscate the crash report?

this is something to work on, but currently I just run the obfuscated baritone jar through fernflower and look at the classess, I can generally recognize what class used to be what source file just from the strings and inheritance structure 😹