[MC-213583] Crash upon importing world generation settings with over 256 layers

The bug

Upon importing world generation settings that include over 256 layers, the game crashes. I've attached the settings file that I used when experiencing the issue, as well as the full crash report.

Note that the world height can be any valid height, and that there must be at least 257 layers included.

How to reproduce

Select Singleplayer → Create New World → More World Options... → Import Settings
Import the

[media]

file
❌ Game crashes

Stack trace

21w03a: [^crash-2021-02-01_16.05.04-client.txt]

Description: mouseClicked event handler

java.lang.ArrayIndexOutOfBoundsException: 256
	at ctz.h(SourceFile:236)
	at ctz.<init>(SourceFile:99)
	at com.mojang.datafixers.util.Function6.lambda$null$4(Function6.java:18)
	at com.mojang.serialization.DataResult$Instance.ap3(DataResult.java:337)
	at com.mojang.serialization.codecs.RecordCodecBuilder$Instance$5.decode(RecordCodecBuilder.java:321)
	at com.mojang.serialization.codecs.RecordCodecBuilder$2.decode(RecordCodecBuilder.java:107)
	at com.mojang.serialization.MapDecoder.lambda$compressedDecode$0(MapDecoder.java:52)
	at com.mojang.serialization.DataResult.lambda$flatMap$10(DataResult.java:138)
	at com.mojang.datafixers.util.Either$Left.map(Either.java:38)
	at com.mojang.serialization.DataResult.flatMap(DataResult.java:136)
	at com.mojang.serialization.MapDecoder.compressedDecode(MapDecoder.java:52)
	at com.mojang.serialization.MapCodec$MapCodecCodec.decode(MapCodec.java:91)
	at com.mojang.serialization.Decoder$1.decode(Decoder.java:49)
	at com.mojang.serialization.Codec$2.decode(Codec.java:71)
	at com.mojang.serialization.Codec$1.decode(Codec.java:45)
	at com.mojang.serialization.Decoder.parse(Decoder.java:18)
	at com.mojang.serialization.codecs.FieldDecoder.decode(FieldDecoder.java:29)
	at com.mojang.serialization.MapCodec$1.decode(MapCodec.java:34)
	at com.mojang.serialization.MapDecoder$4.decode(MapDecoder.java:94)
	at com.mojang.serialization.MapCodec$1.decode(MapCodec.java:34)
	at com.mojang.serialization.codecs.KeyDispatchCodec.lambda$null$1(KeyDispatchCodec.java:67)
	at com.mojang.serialization.DataResult.lambda$flatMap$10(DataResult.java:138)
	at com.mojang.datafixers.util.Either$Left.map(Either.java:38)
	at com.mojang.serialization.DataResult.flatMap(DataResult.java:136)
	at com.mojang.serialization.codecs.KeyDispatchCodec.lambda$decode$2(KeyDispatchCodec.java:58)
	at com.mojang.serialization.DataResult.lambda$flatMap$10(DataResult.java:138)
	at com.mojang.datafixers.util.Either$Left.map(Either.java:38)
	at com.mojang.serialization.DataResult.flatMap(DataResult.java:136)
	at com.mojang.serialization.codecs.KeyDispatchCodec.decode(KeyDispatchCodec.java:56)
	at com.mojang.serialization.MapDecoder.lambda$compressedDecode$0(MapDecoder.java:52)
	at com.mojang.serialization.DataResult.lambda$flatMap$10(DataResult.java:138)
	at com.mojang.datafixers.util.Either$Left.map(Either.java:38)
	at com.mojang.serialization.DataResult.flatMap(DataResult.java:136)
	at com.mojang.serialization.MapDecoder.compressedDecode(MapDecoder.java:52)
	at com.mojang.serialization.MapCodec$MapCodecCodec.decode(MapCodec.java:91)
	at com.mojang.serialization.Decoder.parse(Decoder.java:18)
	at com.mojang.serialization.codecs.FieldDecoder.decode(FieldDecoder.java:29)
	at com.mojang.serialization.MapCodec$1.decode(MapCodec.java:34)
	at com.mojang.serialization.codecs.RecordCodecBuilder$Instance$3.decode(RecordCodecBuilder.java:249)
	at com.mojang.serialization.codecs.RecordCodecBuilder$2.decode(RecordCodecBuilder.java:107)
	at com.mojang.serialization.MapDecoder.lambda$compressedDecode$0(MapDecoder.java:52)
	at com.mojang.serialization.DataResult.lambda$flatMap$10(DataResult.java:138)
	at com.mojang.datafixers.util.Either$Left.map(Either.java:38)
	at com.mojang.serialization.DataResult.flatMap(DataResult.java:136)
	at com.mojang.serialization.MapDecoder.compressedDecode(MapDecoder.java:52)
	at com.mojang.serialization.MapCodec$MapCodecCodec.decode(MapCodec.java:91)
	at com.mojang.serialization.Decoder.parse(Decoder.java:18)
	at com.mojang.serialization.codecs.BaseMapCodec.lambda$decode$2(BaseMapCodec.java:31)
	at java.util.stream.ReduceOps$1ReducingSink.accept(ReduceOps.java:80)
	at java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:193)
	at java.util.Iterator.forEachRemaining(Iterator.java:116)
	at java.util.Spliterators$IteratorSpliterator.forEachRemaining(Spliterators.java:1801)
	at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:481)
	at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:471)
	at java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:708)
	at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
	at java.util.stream.ReferencePipeline.reduce(ReferencePipeline.java:484)
	at com.mojang.serialization.codecs.BaseMapCodec.decode(BaseMapCodec.java:27)
	at com.mojang.serialization.codecs.UnboundedMapCodec.lambda$decode$0(UnboundedMapCodec.java:38)
	at com.mojang.serialization.DataResult.lambda$flatMap$10(DataResult.java:138)
	at com.mojang.datafixers.util.Either$Left.map(Either.java:38)
	at com.mojang.serialization.DataResult.flatMap(DataResult.java:136)
	at com.mojang.serialization.codecs.UnboundedMapCodec.decode(UnboundedMapCodec.java:38)
	at com.mojang.serialization.Decoder$2.decode(Decoder.java:63)
	at com.mojang.serialization.Codec$2.decode(Codec.java:71)
	at vv.decode(SourceFile:33)
	at com.mojang.serialization.Decoder$2.decode(Decoder.java:63)
	at com.mojang.serialization.Codec$2.decode(Codec.java:71)
	at com.mojang.serialization.Decoder.parse(Decoder.java:18)
	at com.mojang.serialization.codecs.FieldDecoder.decode(FieldDecoder.java:29)
	at com.mojang.serialization.MapCodec$1.decode(MapCodec.java:34)
	at com.mojang.serialization.codecs.RecordCodecBuilder$Instance$5.decode(RecordCodecBuilder.java:324)
	at com.mojang.serialization.codecs.RecordCodecBuilder$2.decode(RecordCodecBuilder.java:107)
	at com.mojang.serialization.MapDecoder.lambda$compressedDecode$0(MapDecoder.java:52)
	at com.mojang.serialization.DataResult.lambda$flatMap$10(DataResult.java:138)
	at com.mojang.datafixers.util.Either$Left.map(Either.java:38)
	at com.mojang.serialization.DataResult.flatMap(DataResult.java:136)
	at com.mojang.serialization.MapDecoder.compressedDecode(MapDecoder.java:52)
	at com.mojang.serialization.MapCodec$MapCodecCodec.decode(MapCodec.java:91)
	at com.mojang.serialization.Decoder$1.decode(Decoder.java:49)
	at com.mojang.serialization.Codec$2.decode(Codec.java:71)
	at com.mojang.serialization.Decoder.parse(Decoder.java:18)
	at dye.a(SourceFile:171)
	at dra.b(SourceFile:33)
	at dqu.a(SourceFile:16)
	at dqy.a(SourceFile:153)
	at dry.a(SourceFile:27)
	at dpr.b(SourceFile:92)
	at duk.a(SourceFile:451)
	at dpr.a(SourceFile:92)
	at dpr.c(SourceFile:162)
	at aow.execute(SourceFile:94)
	at dpr.b(SourceFile:162)
	at org.lwjgl.glfw.GLFWMouseButtonCallbackI.callback(GLFWMouseButtonCallbackI.java:36)
	at org.lwjgl.system.JNI.invokeV(Native Method)
	at org.lwjgl.glfw.GLFW.glfwWaitEventsTimeout(GLFW.java:3129)
	at com.mojang.blaze3d.systems.RenderSystem.limitDisplayFPS(SourceFile:140)
	at dpq.e(SourceFile:1076)
	at dpq.e(SourceFile:688)
	at net.minecraft.client.main.Main.main(SourceFile:215)

Linked issues

relates to 2

MC-214780 It is not possible to create a superflat world with over 256 layers Resolved

MC-214290 Crash upon importing world generation settings with a layer that is less than 0 blocks high Resolved

Attachments

213583.json

crash-2021-02-01_16.05.04-client.txt

Comments 1

BBLZ 2021-02-02T10:31:52Z

This might be the same cause issue as MC-68124, that issue was fixed by removing the ability to input > 256 in the in game layer preset menu instead of the underlying issue which is that the flat world generator was never made to be able to generate above 256. which is possible in the latest snapshots.