[22:33:35] [main/INFO] [LaunchWrapper]: Loading tweak class name cpw.mods.fml.common.launcher.FMLTweaker
[22:33:35] [main/INFO] [LaunchWrapper]: Using primary tweak class name cpw.mods.fml.common.launcher.FMLTweaker
[22:33:35] [main/INFO] [LaunchWrapper]: Calling tweak class cpw.mods.fml.common.launcher.FMLTweaker
[22:33:35] [main/INFO] [FML]: Forge Mod Loader version 7.2.125.1034 for Minecraft 1.7.2 loading
[22:33:35] [main/INFO] [FML]: Java is Java HotSpot 64-Bit Server VM, version 1.8.0_31, running on Windows 8.1:amd64:6.3, installed at C:\Program Files\Java\jre1.8.0_31
[22:33:35] [main/INFO] [LaunchWrapper]: Loading tweak class name cpw.mods.fml.common.launcher.FMLInjectionAndSortingTweaker
[22:33:35] [main/INFO] [LaunchWrapper]: Loading tweak class name cpw.mods.fml.common.launcher.FMLDeobfTweaker
[22:33:35] [main/INFO] [LaunchWrapper]: Calling tweak class cpw.mods.fml.common.launcher.FMLInjectionAndSortingTweaker
[22:33:35] [main/ERROR] [LaunchWrapper]: Unable to launch
java.util.ConcurrentModificationException
at java.util.ArrayList$Itr.checkForComodification(Unknown Source) ~[?:1.8.0_31]
at java.util.ArrayList$Itr.remove(Unknown Source) ~[?:1.8.0_31]
at net.minecraft.launchwrapper.Launch.launch(Launch.java:117) [launchwrapper-1.9.jar:?]
at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.9.jar:?]
Picked up _JAVA_OPTIONS: -Xmx4G -Xms2G
Java HotSpot 64-Bit Server VM warning: Using incremental CMS is deprecated and will likely be removed in a future release
This is what I get after I try to run Forge on minecraft.