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
return create((IField)element, flags); 
		}
		return null;
	}
	
	private static boolean updateReferences(int flags) {
		return (flags & UPDATE_REFERENCES) != 0;
	}
	
	private static boolean updateJavadocComments(int flags) {
		return (flags & UPDATE_JAVADOC_COMMENTS) != 0;
	}
	
	private static boolean updateRegularComments(int flags) {
		return (flags & UPDATE_REGULAR_COMMENTS) != 0;
	}
	
	private static boolean updateStringLiterals(int flags) {
		return (flags & UPDATE_STRING_LITERALS) != 0;
	}
	
	private static boolean updateGetterMethod(int flags) {
		return (flags & UPDATE_GETTER_METHOD) != 0;
	}
	
	private static boolean updateSetterMethod(int flags) {
		return (flags & UPDATE_SETTER_METHOD) != 0;
	}
}