added a probe code.

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@3620 71c3de6d-444a-0410-be80-ed276b4c234a

core/src/main/java/hudson/maven/MavenModuleSetBuild.java

@@ -15,6 +15,7 @@ import org.apache.maven.project.ProjectBuildingException;
 
 import java.io.File;
 import java.io.IOException;
+import java.io.PrintStream;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.HashMap;
@@ -244,6 +245,10 @@ public final class MavenModuleSetBuild extends AbstractBuild<MavenModuleSet,Mave
             } catch (RuntimeException e) {
                 // bug in the code.
                 e.printStackTrace(listener.error("Processing failed due to a bug in the code. Please report thus to users@hudson.dev.java.net"));
+                PrintStream logger = listener.getLogger();
+                logger.println("project="+project);
+                logger.println("project.getModules()="+project.getModules());
+                logger.println("project.getRootModule()="+project.getRootModule());
                 throw e;
             }
         }