Index: lucene/tools/build.xml
===================================================================
--- lucene/tools/build.xml	(revision 1416008)
+++ lucene/tools/build.xml	(working copy)
@@ -26,7 +26,7 @@
 
   <path id="classpath">
     <fileset dir="lib">
-      <include name="asm-debug-all-4.0.jar"/>
+      <include name="asm-debug-all-4.1.jar"/>
     </fileset>
   </path>
 
Index: lucene/tools/custom-tasks.xml
===================================================================
--- lucene/tools/custom-tasks.xml	(revision 1416008)
+++ lucene/tools/custom-tasks.xml	(working copy)
@@ -10,7 +10,7 @@
     <taskdef resource="lucene-solr.antlib.xml">
       <classpath>
         <pathelement location="${custom-tasks.dir}/../build/tools/classes/java" />
-        <fileset dir="${custom-tasks.dir}/lib" includes="asm-debug-all-4.0.jar" />
+        <fileset dir="${custom-tasks.dir}/lib" includes="asm-debug-all-4.1.jar" />
       </classpath>
     </taskdef>
     <property name="custom-tasks.loaded" value="true"/>
Index: lucene/tools/ivy.xml
===================================================================
--- lucene/tools/ivy.xml	(revision 1416008)
+++ lucene/tools/ivy.xml	(working copy)
@@ -23,7 +23,7 @@
        We use the asm-debug-all library, as the as-all has no generics.
        It's not really debug, just not "stripped":
       -->
-      <dependency org="org.ow2.asm" name="asm-debug-all" rev="4.0" transitive="false"/>
+      <dependency org="org.ow2.asm" name="asm-debug-all" rev="4.1" transitive="false"/>
       <exclude org="*" ext="*" matcher="regexp" type="${ivy.exclude.types}"/> 
     </dependencies>
 </ivy-module>
Index: lucene/tools/src/java/org/apache/lucene/validation/ForbiddenApisCheckTask.java
===================================================================
--- lucene/tools/src/java/org/apache/lucene/validation/ForbiddenApisCheckTask.java	(revision 1416008)
+++ lucene/tools/src/java/org/apache/lucene/validation/ForbiddenApisCheckTask.java	(working copy)
@@ -315,6 +315,16 @@
   
   @Override
   public void execute() throws BuildException {
+    // the checker is not compatible with JDK 1.8+ (changed class format: 52.0), don't fail just report warning:
+    try {
+      Collections.class.getMethod("emptySortedSet");
+      // this is Java 8 :(
+      log("Java 8 or later is currently not supported by this checker. Please run the checks with a previous JDK!", Project.MSG_WARN);
+      return;
+    } catch (NoSuchMethodException nsme) {
+      // ignore, we are fine!
+    }
+    
     AntClassLoader antLoader = null;
     try {
       if (classpath != null) {