The complete log:
[17:20:57] [Client thread/INFO]: Setting user: erUzama
[17:20:57] [Client thread/INFO]: (Session ID is token:d06762950e66498eb8d341acfb819a7e:3262a6868a24419a8b97bd3c8b7fe697)
[17:21:01] [Client thread/INFO]: LWJGL Version: 2.9.4
[17:21:02] [Client thread/INFO]: Reloading ResourceManager: Default
If on Windows, make sure to provide all of the necessary dll's as specified in the twitchsdk README. Also, make sure to set the PATH environment variable to point to the directory containing the dll's.
[17:21:02] [Client thread/ERROR]: Couldn't initialize twitch stream
[17:21:02] [Sound Library Loader/INFO]: Starting up SoundSystem...
[17:21:02] [Thread-6/INFO]: Initializing LWJGL OpenAL
[17:21:02] [Thread-6/INFO]: (The LWJGL binding of OpenAL. For more information, see http://www.lwjgl.org)
[17:21:02] [Thread-6/INFO]: OpenAL initialized.
[17:21:03] [Sound Library Loader/INFO]: Sound engine started
[17:21:08] [Client thread/INFO]: Created: 512x512 textures-atlas
[17:21:16] [Server thread/INFO]: Starting integrated minecraft server version 1.8.7
[17:21:16] [Server thread/INFO]: Generating keypair
[17:21:17] [Server thread/INFO]: Preparing start region for level 0
[17:21:18] [Server thread/INFO]: Preparing spawn area: 18%
[17:21:19] [Server thread/INFO]: Preparing spawn area: 81%
[17:21:19] [Server thread/INFO]: Changing view distance to 12, from 10
[17:21:20] [Server thread/INFO]: erUzama[local:E:f3995898] logged in with entity id 177 at (-73.77959491976293, 69.0, -181.3895933972893)
[17:21:20] [Server thread/INFO]: erUzama se ha unido a la partida
[17:21:23] [Server thread/WARN]: Can't keep up! Did the system time change, or is the server overloaded? Running 3172ms behind, skipping 63 tick(s)
[17:21:23] [Server thread/INFO]: Saving and pausing game...
[17:21:23] [Server thread/INFO]: Saving chunks for level 'RaynbowLand'/Overworld
[17:21:23] [Client thread/FATAL]: Error executing task
java.util.concurrent.ExecutionException: java.lang.StringIndexOutOfBoundsException: String index out of range: 2
at java.util.concurrent.FutureTask.report(FutureTask.java:122) ~[?:1.7.0_79]
at java.util.concurrent.FutureTask.get(FutureTask.java:188) ~[?:1.7.0_79]
at g.a(SourceFile:61) [1.8.7.jar:?]
at ave.av(SourceFile:880) [1.8.7.jar:?]
at ave.a(SourceFile:325) [1.8.7.jar:?]
at net.minecraft.client.main.Main.main(SourceFile:124) [1.8.7.jar:?]
Caused by: java.lang.StringIndexOutOfBoundsException: String index out of range: 2
at java.lang.String.substring(String.java:1907) ~[?:1.7.0_79]
at bnp.a(SourceFile:65) ~[1.8.7.jar:?]
at bnp$3$1.run(SourceFile:114) ~[1.8.7.jar:?]
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471) ~[?:1.7.0_79]
at java.util.concurrent.FutureTask.run(FutureTask.java:262) ~[?:1.7.0_79]
at g.a(SourceFile:60) ~[1.8.7.jar:?]
... 3 more
[17:21:25] [Server thread/INFO]: Saving chunks for level 'RaynbowLand'/Nether
[17:21:25] [Server thread/INFO]: Saving chunks for level 'RaynbowLand'/The End
Failed to open BO for returned DRI2 buffer (854x480, dri2 back buffer, named 11).
This is likely a bug in the X Server that will lead to a crash soon.
#
# A fatal error has been detected by the Java Runtime Environment:
#
# SIGSEGV (0xb) at pc=0x00007f45aa772f8d, pid=8552, tid=139938498336512
#
# JRE version: OpenJDK Runtime Environment (7.0_79-b14) (build 1.7.0_79-b14)
# Java VM: OpenJDK 64-Bit Server VM (24.79-b02 mixed mode linux-amd64 compressed oops)
# Derivative: IcedTea 2.5.5
# Distribution: Custom build (Fri May 15 21:00:36 UTC 2015)
# Problematic frame:
# C [i965_dri.so+0x3a0f8d]
#
# Failed to write core dump. Core dumps have been disabled. To enable core dumping, try "ulimit -c unlimited" before starting Java again
#
# An error report file with more information is saved as:
# /home/eruzama/.minecraft/hs_err_pid8552.log
#
# If you would like to submit a bug report, please include
# instructions on how to reproduce the bug and visit:
# http://icedtea.classpath.org/bugzilla
# The crash happened outside the Java Virtual Machine in native code.
# See problematic frame for where to report the bug.
#