The bug
It appears teleporting a player to unloaded chunks as an entity inside a function run as gameLoopFunction causes the server to hang.
Possibly related error message (17w48a)
21:58:22] [Server thread/FATAL]: Error executing task
java.util.concurrent.ExecutionException: java.lang.NegativeArraySizeException: nbits < 0: -1611584737
at java.util.concurrent.FutureTask.report(Unknown Source) ~[?:1.8.0_151]
at java.util.concurrent.FutureTask.get(Unknown Source) ~[?:1.8.0_151]
at h.a(SourceFile:124) [17w48a.jar:?]
at net.minecraft.server.MinecraftServer.w(SourceFile:632) [17w48a.jar:?]
at net.minecraft.server.MinecraftServer.v(SourceFile:588) [17w48a.jar:?]
at ckz.v(SourceFile:152) [17w48a.jar:?]
at net.minecraft.server.MinecraftServer.run(SourceFile:493) [17w48a.jar:?]
at java.lang.Thread.run(Unknown Source) [?:1.8.0_151]
Caused by: java.lang.NegativeArraySizeException: nbits < 0: -1611584737
at java.util.BitSet.<init>(Unknown Source) ~[?:1.8.0_151]
at blb.<init>(SourceFile:22) ~[17w48a.jar:?]
at blb.<init>(SourceFile:17) ~[17w48a.jar:?]
at aqg.a(SourceFile:1019) ~[17w48a.jar:?]
at aqg.a(SourceFile:1124) ~[17w48a.jar:?]
at aqg.a(SourceFile:1108) ~[17w48a.jar:?]
at yr.a(SourceFile:636) ~[17w48a.jar:?]
at qy.a(SourceFile:524) ~[17w48a.jar:?]
at ku.a(SourceFile:126) ~[17w48a.jar:?]
at ku$b.a(SourceFile:18) ~[17w48a.jar:?]
at hc$1.run(SourceFile:13) ~[17w48a.jar:?]
at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) ~[?:1.8.0_151]
at java.util.concurrent.FutureTask.run(Unknown Source) ~[?:1.8.0_151]
at h.a(SourceFile:123) ~[17w48a.jar:?]
... 5 more
How to reproduce
- Download the attached datapack MC_119549_datapack.zip and place it in the datapacks folder of your world
- Open the world and run the following commands
/gamerule gameLoopFunction custom:teleport /summon armor_stand ~ ~ ~ {CustomName:"Test"}