I was attempting to update my dev environment to 1.12.2 (from 1.12.1, which worked perfectly) and kept getting an error when using

gradlew setupDecompWorkspace

 

During the :decompileMc process, I would get this error:

Spoiler

:decompileMc
Exception in thread "main" java.lang.IndexOutOfBoundsException: Index: 24, Size: 9
        at java.util.ArrayList.rangeCheck(ArrayList.java:653)
        at java.util.ArrayList.get(ArrayList.java:429)
        at org.jetbrains.java.decompiler.struct.consts.ConstantPool.<init>(ConstantPool.java:109)
        at org.jetbrains.java.decompiler.struct.StructClass.<init>(StructClass.java:84)
        at org.jetbrains.java.decompiler.struct.StructClass.<init>(StructClass.java:72)
        at org.jetbrains.java.decompiler.struct.StructContext.addArchive(StructContext.java:159)
        at org.jetbrains.java.decompiler.struct.StructContext.addSpace(StructContext.java:100)
        at org.jetbrains.java.decompiler.struct.StructContext.addSpace(StructContext.java:78)
        at org.jetbrains.java.decompiler.main.Fernflower.addAllClasspath(Fernflower.java:119)
        at org.jetbrains.java.decompiler.main.Fernflower.<init>(Fernflower.java:47)
        at org.jetbrains.java.decompiler.main.decompiler.BaseDecompiler.<init>(BaseDecompiler.java:32)
        at net.minecraftforge.gradle.tasks.fernflower.FernFlowerInvoker.runFernFlower(FernFlowerInvoker.java:64)
        at net.minecraftforge.gradle.tasks.fernflower.FernFlowerInvoker.main(FernFlowerInvoker.java:41)
:decompileMc FAILED

 

 

My JAVA_HOME is correctly set, I'm using JDK 1.8 64 bit, everything worked perfectly fine just as I had it with 1.12.1.

 

Anyone know why this is happening, and if I can do anything to fix it?

Edited September 25, 20178 yr by Shnupbups100

So I just came over here to ask about exact same issue that I am suddenly getting with a project that I am pretty sure I didn't get last time I updated to 1.12. 

 

For your reference the build file that I am using https://github.com/P3pp3rF1y/Reliquary/blob/1.12.x/build.gradle 

 

I suspect this issue may have something to do with a recent update to FG?

FYI, this was resolved in https://github.com/MinecraftForge/ForgeGradle/issues/451. Just do gradlew cleanCache setupDecompWorkspace --refresh-dependencies and you should be good.