title: How to find the problem when a maven packaging stage last indefinitely?
body: <p>I have a fairly large maven project that if compiled (using <code>mvn package</code> or <code>mvn install</code>), stuck on a packaging stage for 10+ hours:</p>
  <pre><code>[INFO] Building jar: /home/peng/git-dev/scala-2.11/datapassports/spookystuff/mldsl/target/spookystuff-mldsl-0.6.2-SNAPSHOT-javadoc.jar
  [INFO] 
  [INFO] --- maven-source-plugin:3.1.0:jar-no-fork (attach-sources) @ spookystuff-mldsl ---
  [INFO] Building jar: /home/peng/git-dev/scala-2.11/datapassports/spookystuff/mldsl/target/spookystuff-mldsl-0.6.2-SNAPSHOT-sources.jar
  [INFO] 
  [INFO] --- maven-source-plugin:3.1.0:test-jar-no-fork (attach-sources) @ spookystuff-mldsl ---
  [INFO] Building jar: /home/peng/git-dev/scala-2.11/datapassports/spookystuff/mldsl/target/spookystuff-mldsl-0.6.2-SNAPSHOT-test-sources.jar
  [INFO] 
  [INFO] --- maven-jar-plugin:3.0.2:test-jar (default) @ spookystuff-mldsl ---
  [INFO] Building jar: /home/peng/git-dev/scala-2.11/datapassports/spookystuff/mldsl/target/spookystuff-mldsl-0.6.2-SNAPSHOT-tests.jar
  [INFO] 
  [INFO] --- maven-install-plugin:2.5.2:install (default-install) @ spookystuff-mldsl ---
  [INFO] Installing /home/peng/git-dev/scala-2.11/datapassports/spookystuff/mldsl/target/spookystuff-mldsl-0.6.2-SNAPSHOT.jar to /home/peng/.m2/repository/com/tribbloids/spookystuff/spookystuff-mldsl/0.6.2-SNAPSHOT/spookystuff-mldsl-0.6.2-SNAPSHOT.jar
  [INFO] Installing /home/peng/git-dev/scala-2.11/datapassports/spookystuff/mldsl/.flattened-pom.xml to /home/peng/.m2/repository/com/tribbloids/spookystuff/spookystuff-mldsl/0.6.2-SNAPSHOT/spookystuff-mldsl-0.6.2-SNAPSHOT.pom
  [INFO] Installing /home/peng/git-dev/scala-2.11/datapassports/spookystuff/mldsl/target/spookystuff-mldsl-0.6.2-SNAPSHOT-javadoc.jar to /home/peng/.m2/repository/com/tribbloids/spookystuff/spookystuff-mldsl/0.6.2-SNAPSHOT/spookystuff-mldsl-0.6.2-SNAPSHOT-javadoc.jar
  [INFO] Installing /home/peng/git-dev/scala-2.11/datapassports/spookystuff/mldsl/target/spookystuff-mldsl-0.6.2-SNAPSHOT-sources.jar to /home/peng/.m2/repository/com/tribbloids/spookystuff/spookystuff-mldsl/0.6.2-SNAPSHOT/spookystuff-mldsl-0.6.2-SNAPSHOT-sources.jar
  [INFO] Installing /home/peng/git-dev/scala-2.11/datapassports/spookystuff/mldsl/target/spookystuff-mldsl-0.6.2-SNAPSHOT-test-sources.jar to /home/peng/.m2/repository/com/tribbloids/spookystuff/spookystuff-mldsl/0.6.2-SNAPSHOT/spookystuff-mldsl-0.6.2-SNAPSHOT-test-sources.jar
  [INFO] Installing /home/peng/git-dev/scala-2.11/datapassports/spookystuff/mldsl/target/spookystuff-mldsl-0.6.2-SNAPSHOT-tests.jar to /home/peng/.m2/repository/com/tribbloids/spookystuff/spookystuff-mldsl/0.6.2-SNAPSHOT/spookystuff-mldsl-0.6.2-SNAPSHOT-tests.jar
  (this is the last line of output)
  </code></pre>
  <p>The build output can be observed on CI server, with similar output:</p>
  <p><a href="https://app.codeship.com/projects/166836/builds/48698210?pipeline=103aace8-047a-47e4-9cb9-018c3ce0693a" rel="nofollow noreferrer">https://app.codeship.com/projects/166836/builds/48698210?pipeline=103aace8-047a-47e4-9cb9-018c3ce0693a</a></p>
  <p>I don't know what have caused this behaviour, but I suspect that a bug in maven-shade-plugin has caused dependency reduced pom generation to move into a indefinitely loop. How can I confirm this hypothesis collect enough evidence to report to the plugin maintainers?</p>