title: Gradle build error: Cannot get property 'dirName' on null object
body: <p>I am getting gradle build error:</p>
  
  <pre><code>Error: Cannot get property 'dirName' on null object
  </code></pre>
  
  <p>I get this error with gradle version 1.3.1 or greater.</p>
  
  <p>When I use gradle version 1.2.3 there is no error.</p>
  
  <p>I google this error but was not able to find any solution. Please help!</p>
  
  <p>My project gradle file:</p>
  
  <pre><code>// Top-level build file where you can add configuration options common to all sub-projects/modules.
  
  buildscript {
      repositories {
          maven { url "http://dl.bintray.com/populov/maven"  }
          mavenCentral()
          jcenter()
          flatDir { dirs '/usr/local/DexGuard6.1.19/lib' }
      }
      dependencies {
          classpath 'com.android.tools.build:gradle:1.2.3'
          classpath ':dexguard:'
  
          // NOTE: Do not place your application dependencies here; they belong
          // in the individual module build.gradle files
      } 
  }
  
  allprojects {
      repositories {
          maven { url "http://dl.bintray.com/populov/maven" }
          maven { url "https://repo.commonsware.com.s3.amazonaws.com" }
          maven { url 'https://maven.fabric.io/public' }
          maven { url "https://jitpack.io" }
          mavenCentral()
          jcenter()
      }
  }
  </code></pre>