I am getting a crash when I break any block in my existing world. I thought this was with the GT++ redstone cable but I noticed when I broke dirt and stone. I appears to be in the harvestdrops function for GT++:

Note: System information is psoted in the redstone cable issue #133
---- Minecraft Crash Report ----
// Who set us up the TNT?

Time: 10/3/17 8:42 PM
Description: Ticking memory connection

java.lang.IndexOutOfBoundsException: Index: 0, Size: 0
at java.util.ArrayList.rangeCheck(ArrayList.java:653)
at java.util.ArrayList.get(ArrayList.java:429)
at net.minecraftforge.oredict.OreDictionary$UnmodifiableArrayList.get(OreDictionary.java:630)
at gtPlusPlus.core.handler.events.BlockEventHandler.harvestDrops(BlockEventHandler.java:123)
at cpw.mods.fml.common.eventhandler.ASMEventHandler_598_BlockEventHandler_harvestDrops_HarvestDropsEvent.invoke(.dynamic)
at cpw.mods.fml.common.eventhandler.ASMEventHandler.invoke(ASMEventHandler.java:54)
at cpw.mods.fml.common.eventhandler.EventBus.post(EventBus.java:140)
at net.minecraftforge.event.ForgeEventFactory.fireBlockHarvesting(ForgeEventFactory.java:162)
at net.minecraft.block.Block.func_149690_a(Block.java:656)
at net.minecraft.block.Block.func_149697_b(Block.java:648)
at net.minecraft.block.Block.func_149636_a(Block.java:974)
at net.minecraft.server.management.ItemInWorldManager.func_73084_b(ItemInWorldManager.java:299)
at net.minecraft.server.management.ItemInWorldManager.func_73082_a(ItemInWorldManager.java:217)
at net.minecraft.network.NetHandlerPlayServer.func_147345_a(NetHandlerPlayServer.java:498)
at net.minecraft.network.play.client.C07PacketPlayerDigging.func_148833_a(SourceFile:53)
at net.minecraft.network.play.client.C07PacketPlayerDigging.func_148833_a(SourceFile:8)
at net.minecraft.network.NetworkManager.func_74428_b(NetworkManager.java:212)
at net.minecraft.network.NetworkSystem.func_151269_c(NetworkSystem.java:165)
at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:659)
at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:547)
at net.minecraft.server.integrated.IntegratedServer.func_71217_p(IntegratedServer.java:111)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:396)
at net.minecraft.server.MinecraftServer$2.run(MinecraftServer.java:685)

A detailed walkthrough of the error, its code path and all known details is as follows:

-- Head --
Stacktrace:
at java.util.ArrayList.rangeCheck(ArrayList.java:653)
at java.util.ArrayList.get(ArrayList.java:429)
at net.minecraftforge.oredict.OreDictionary$UnmodifiableArrayList.get(OreDictionary.java:630)
at gtPlusPlus.core.handler.events.BlockEventHandler.harvestDrops(BlockEventHandler.java:123)
at cpw.mods.fml.common.eventhandler.ASMEventHandler_598_BlockEventHandler_harvestDrops_HarvestDropsEvent.invoke(.dynamic)
at cpw.mods.fml.common.eventhandler.ASMEventHandler.invoke(ASMEventHandler.java:54)
at cpw.mods.fml.common.eventhandler.EventBus.post(EventBus.java:140)
at net.minecraftforge.event.ForgeEventFactory.fireBlockHarvesting(ForgeEventFactory.java:162)
at net.minecraft.block.Block.func_149690_a(Block.java:656)
at net.minecraft.block.Block.func_149697_b(Block.java:648)
at net.minecraft.block.Block.func_149636_a(Block.java:974)
at net.minecraft.server.management.ItemInWorldManager.func_73084_b(ItemInWorldManager.java:299)
at net.minecraft.server.management.ItemInWorldManager.func_73082_a(ItemInWorldManager.java:217)
at net.minecraft.network.NetHandlerPlayServer.func_147345_a(NetHandlerPlayServer.java:498)
at net.minecraft.network.play.client.C07PacketPlayerDigging.func_148833_a(SourceFile:53)
at net.minecraft.network.play.client.C07PacketPlayerDigging.func_148833_a(SourceFile:8)
at net.minecraft.network.NetworkManager.func_74428_b(NetworkManager.java:212)
at net.minecraft.network.NetworkSystem.func_151269_c(NetworkSystem.java:165)

-- Ticking connection --
Details:
Connection: net.minecraft.network.NetworkManager@5587135f
Stacktrace:
at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:659)
at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:547)
at net.minecraft.server.integrated.IntegratedServer.func_71217_p(IntegratedServer.java:111)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:396)
at net.minecraft.server.MinecraftServer$2.run(MinecraftServer.java:685)

I informed alkalus bout this too

GTNewHorizons/GTplusplus@45cd375

This commit in our fork fixes it