Bug 27878 infinite loop?
build N1206 on Win2K, IBM VM 1.3.1 in the big workspace I started up, opened the java perspective and navigated to org.eclipse.core.resources/src. When I clicked to expand the src folder my CPU went to 100% for alone time (forever?). Using ctrl-break I got the attached core dump which indicates that the RenameSupport.create() method appears to be called infinitely. Note that memory use does not seem to be increasing.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/ui/refactoring/RenameSupport.java
import org.eclipse.jdt.internal.corext.refactoring.rename.RenamePackageRefactoring;
import org.eclipse.jdt.internal.corext.refactoring.rename.RenameTypeRefactoring;
import org.eclipse.jdt.internal.ui.refactoring.RefactoringSupport;
import org.eclipse.jdt.internal.ui.reorg.IRefactoringRenameSupport;
/**
 * Central access point to launch rename refactorings. Refactorings triggered
 * through this class will perform the following steps:
 * <ul>
 *   <li>check if the element can be renamed</li>
 *   <li>save all unsaved files</li>
 *   <li>open a corresponding refactoring dialog to gather user input</li>
 *   <li>execute or cancel the refactoring depending on user action</li>
 * </ul>
 * 
 * @since 2.1
 */
public class RenameSupport {
	private IRefactoringRenameSupport fSupport;
	private IJavaElement fElement;
	
	/**
	 * Checks whether the rename support can actually rename the Java
	 * element passed to the create method.
	 * @return <code>true</code> if the element can be renamed; otherwise
	 * <code>false</code> is returned.
	 * @throws CoreException if an unexpected exception occurs while checking
	 * renaming.
	 */
	public boolean canRename() throws CoreException {
		return fSupport.canRename(fElement);