title: How to debug Unhandled exception / Segmentation error in IBM Bluemix Delivery Pipeline
body: <p>I've created a toolchain in IBM Bluemix DevOps and it has a Delivery Pipeline app. 
  In a stage I'm trying to install and run SBT, but I'm facing with an issue. Unfortunately based on the logs I cannot figure out what the problem is, it just tells that Unhandled exception occurred, segmentation error and some kind of internal stacktrace. </p>
  
  <p><strong>How could I debug what's happening in the container belongs to this job?</strong></p>
  
  <p>Here's the console log for the job:</p>
  
  <pre><code>[info] Compiling 11 Scala sources and 7 Java sources to /home/pipeline/ebd42c4b-9442-4194-9ea7-628ad43d2d4e/target/scala-2.12/classes...
  [info] 'compiler-interface' not yet compiled for Scala 2.12.2. Compiling...
  #0: /opt/IBM/ibm-java-x86_64-80/jre/lib/amd64/compressedrefs/libj9jit28.so(+0x8cfb1f) [0x7fc7d2010b1f]
  #1: /opt/IBM/ibm-java-x86_64-80/jre/lib/amd64/compressedrefs/libj9jit28.so(+0x1095d1) [0x7fc7d184a5d1]
  #2: /opt/IBM/ibm-java-x86_64-80/jre/lib/amd64/compressedrefs/libj9prt28.so(+0x3ec7e) [0x7fc7d3bc8c7e]
  #3: /lib/x86_64-linux-gnu/libpthread.so.0(+0x10330) [0x7fc7da246330]
  #4: /opt/IBM/ibm-java-x86_64-80/jre/lib/amd64/compressedrefs/libj9jit28.so(+0x3374f3) [0x7fc7d1a784f3]
  #5: /opt/IBM/ibm-java-x86_64-80/jre/lib/amd64/compressedrefs/libj9jit28.so(+0x33a7ef) [0x7fc7d1a7b7ef]
  #6: /opt/IBM/ibm-java-x86_64-80/jre/lib/amd64/compressedrefs/libj9jit28.so(+0x33b9ff) [0x7fc7d1a7c9ff]
  #7: /opt/IBM/ibm-java-x86_64-80/jre/lib/amd64/compressedrefs/libj9jit28.so(+0x5c0ac1) [0x7fc7d1d01ac1]
  #8: /opt/IBM/ibm-java-x86_64-80/jre/lib/amd64/compressedrefs/libj9jit28.so(+0x2ee81d) [0x7fc7d1a2f81d]
  #9: /opt/IBM/ibm-java-x86_64-80/jre/lib/amd64/compressedrefs/libj9jit28.so(+0x2eeb41) [0x7fc7d1a2fb41]
  #10: /opt/IBM/ibm-java-x86_64-80/jre/lib/amd64/compressedrefs/libj9jit28.so(+0x2efdb4) [0x7fc7d1a30db4]
  #11: /opt/IBM/ibm-java-x86_64-80/jre/lib/amd64/compressedrefs/libj9jit28.so(+0x7eb5bb) [0x7fc7d1f2c5bb]
  #12: /opt/IBM/ibm-java-x86_64-80/jre/lib/amd64/compressedrefs/libj9jit28.so(+0x7f2f8c) [0x7fc7d1f33f8c]
  #13: /opt/IBM/ibm-java-x86_64-80/jre/lib/amd64/compressedrefs/libj9jit28.so(+0x11158d) [0x7fc7d185258d]
  #14: /opt/IBM/ibm-java-x86_64-80/jre/lib/amd64/compressedrefs/libj9jit28.so(+0x112aa0) [0x7fc7d1853aa0]
  #15: /opt/IBM/ibm-java-x86_64-80/jre/lib/amd64/compressedrefs/libj9prt28.so(+0x3f005) [0x7fc7d3bc9005]
  #16: /opt/IBM/ibm-java-x86_64-80/jre/lib/amd64/compressedrefs/libj9jit28.so(+0x114cc0) [0x7fc7d1855cc0]
  #17: /opt/IBM/ibm-java-x86_64-80/jre/lib/amd64/compressedrefs/libj9jit28.so(+0x115926) [0x7fc7d1856926]
  #18: /opt/IBM/ibm-java-x86_64-80/jre/lib/amd64/compressedrefs/libj9prt28.so(+0x3f005) [0x7fc7d3bc9005]
  #19: /opt/IBM/ibm-java-x86_64-80/jre/lib/amd64/compressedrefs/libj9jit28.so(+0x1161f4) [0x7fc7d18571f4]
  #20: /opt/IBM/ibm-java-x86_64-80/jre/lib/amd64/compressedrefs/libj9thr28.so(+0x99cc) [0x7fc7d81e89cc]
  #21: /lib/x86_64-linux-gnu/libpthread.so.0(+0x8184) [0x7fc7da23e184]
  #22: function clone+0x6d [0x7fc7d9b4fffd]
  Unhandled exception
  Type=Segmentation error vmState=0x000529ff
  J9Generic_Signal_Number=00000004 Signal_Number=0000000b Error_Value=00000000 Signal_Code=00000001
  Handler1=00007FC7D8470140 Handler2=00007FC7D3BC8A80 InaccessibleAddress=0000000000000010
  RDI=0000000000000000 RSI=0000000000000000 RAX=0000000000000000 RBX=00007FC7ADDA8F18
  RCX=0000000000000000 RDX=0000000000000000 R8=0000000000000000 R9=0000000000000000
  R10=0000100000000000 R11=00007FC7BFD69858 R12=00007FC7CE18A6B8 R13=00007FC7CE1AD208
  R14=00007FC7ADD19158 R15=0000000000000001
  RIP=00007FC7D1A784F3 GS=0000 FS=0000 RSP=00007FC7CEDD3510
  EFlags=0000000000210246 CS=E033 RBP=00007FC7ADD18E48 ERR=0000000000000004
  TRAPNO=000000000000000E OLDMASK=0000000000000000 CR2=0000000000000010
  xmm0 3ff0000000000000 (f: 0.000000, d: 1.000000e+00)
  xmm1 3ff0000000000000 (f: 0.000000, d: 1.000000e+00)
  xmm2 3ff0000000000000 (f: 0.000000, d: 1.000000e+00)
  xmm3 0269026802670266 (f: 40305256.000000, d: 4.780106e-297)
  xmm4 02710270026f026e (f: 40829552.000000, d: 6.502141e-297)
  xmm5 0279027802770276 (f: 41353848.000000, d: 9.560306e-297)
  xmm6 02810280027f027e (f: 41878144.000000, d: 1.300447e-296)
  xmm7 0289028802870286 (f: 42402440.000000, d: 1.912080e-296)
  xmm8 0000000000000000 (f: 0.000000, d: 0.000000e+00)
  xmm9 0299029802970296 (f: 43451032.000000, d: 3.824197e-296)
  xmm10 000000000000ff00 (f: 65280.000000, d: 3.225261e-319)
  xmm11 0000000000000000 (f: 0.000000, d: 0.000000e+00)
  xmm12 0000000000000000 (f: 0.000000, d: 0.000000e+00)
  xmm13 0000000000000000 (f: 0.000000, d: 0.000000e+00)
  xmm14 0000000000000000 (f: 0.000000, d: 0.000000e+00)
  xmm15 4032b70887231f40 (f: 2267225856.000000, d: 1.871497e+01)
  Module=/opt/IBM/ibm-java-x86_64-80/jre/lib/amd64/compressedrefs/libj9jit28.so
  Module_base_address=00007FC7D1741000
  
  Method_being_compiled=scala/collection/mutable/FlatHashTable.addElem(Ljava/lang/Object;)Z
  Target=2_80_20170516_348050 (Linux 4.4.0-59-generic)
  CPU=amd64 (16 logical CPUs) (0x7d6cfb000 RAM)
  ----------- Stack Backtrace -----------
  (0x00007FC7D1A784F3 [libj9jit28.so+0x3374f3])
  (0x00007FC7D1A7B7EF [libj9jit28.so+0x33a7ef])
  (0x00007FC7D1A7C9FF [libj9jit28.so+0x33b9ff])
  (0x00007FC7D1D01AC1 [libj9jit28.so+0x5c0ac1])
  (0x00007FC7D1A2F81D [libj9jit28.so+0x2ee81d])
  (0x00007FC7D1A2FB41 [libj9jit28.so+0x2eeb41])
  (0x00007FC7D1A30DB4 [libj9jit28.so+0x2efdb4])
  (0x00007FC7D1F2C5BB [libj9jit28.so+0x7eb5bb])
  (0x00007FC7D1F33F8C [libj9jit28.so+0x7f2f8c])
  (0x00007FC7D185258D [libj9jit28.so+0x11158d])
  (0x00007FC7D1853AA0 [libj9jit28.so+0x112aa0])
  (0x00007FC7D3BC9005 [libj9prt28.so+0x3f005])
  (0x00007FC7D1855CC0 [libj9jit28.so+0x114cc0])
  (0x00007FC7D1856926 [libj9jit28.so+0x115926])
  (0x00007FC7D3BC9005 [libj9prt28.so+0x3f005])
  (0x00007FC7D18571F4 [libj9jit28.so+0x1161f4])
  (0x00007FC7D81E89CC [libj9thr28.so+0x99cc])
  (0x00007FC7DA23E184 [libpthread.so.0+0x8184])
  clone+0x6d (0x00007FC7D9B4FFFD [libc.so.6+0xfdffd])
  ---------------------------------------
  JVMDUMP039I Processing dump event "gpf", detail "" at 2017/08/24 12:25:10 - please wait.
  JVMDUMP032I JVM requested System dump using '/home/pipeline/ebd42c4b-9442-4194-9ea7-628ad43d2d4e/core.20170824.122510.163.0001.dmp' in response to an event
  JVMPORT030W /proc/sys/kernel/core_pattern setting "|/usr/share/apport/apport %p %s %c %P" specifies that the core dump is to be piped to an external program.  Attempting to rename either core or core.941.
  </code></pre>
  
  <p><strong>Update:</strong> Commands I've executed</p>
  
  <pre><code>#!/bin/bash
  wget --output-document=/tmp/sbt.tgz             
  https://github.com/sbt/sbt/releases/download/v0.13.15/sbt-0.13.15.tgz
  tar -xvf /tmp/sbt.tgz --directory=/tmp
  export PATH="/tmp/sbt/bin:$PATH"
  chmod +x /tmp/sbt
  
  export JAVA_HOME=$JAVA8_HOME
  export PATH="$JAVA_HOME/bin/:$PATH"    
  
  sbt compile
  </code></pre>