Index: src/runtime/class.m
==================================================================
--- src/runtime/class.m
+++ src/runtime/class.m
@@ -581,12 +581,12 @@
 object_getClassName(id obj)
 {
 	return object_getClass(obj)->name;
 }
 
-static void
-free_class(Class rcls)
+void
+objc_free_class(Class rcls)
 {
 	struct objc_abi_class *cls = (struct objc_abi_class*)rcls;
 
 	if (rcls->subclass_list != NULL) {
 		free(rcls->subclass_list);
@@ -598,10 +598,12 @@
 
 	rcls->dtable = NULL;
 
 	if (rcls->superclass != Nil)
 		cls->superclass = rcls->superclass->name;
+
+	objc_hashtable_set(classes, cls->name, NULL);
 }
 
 void
 objc_free_all_classes(void)
 {
@@ -610,13 +612,23 @@
 	if (classes == NULL)
 		return;
 
 	for (i = 0; i <= classes->last_idx; i++) {
 		if (classes->data[i] != NULL) {
-			free_class((Class)classes->data[i]->obj);
-			free_class(((Class)classes->data[i]->obj)->isa);
+			Class cls = classes->data[i]->obj;
+
+			if (cls == Nil)
+				continue;
+
+			objc_free_class(cls);
+			objc_free_class(cls->isa);
 		}
 	}
+
+	if (empty_dtable != NULL) {
+		objc_sparsearray_free(empty_dtable);
+		empty_dtable = NULL;
+	}
 
 	objc_hashtable_free(classes);
 	classes = NULL;
 }

Index: src/runtime/runtime-private.h
==================================================================
--- src/runtime/runtime-private.h
+++ src/runtime/runtime-private.h
@@ -128,10 +128,11 @@
 extern void objc_free_all_categories(void);
 extern void objc_initialize_class(Class);
 extern void objc_update_dtable(Class);
 extern void objc_register_all_classes(struct objc_abi_symtab*);
 extern Class objc_classname_to_class(const char*);
+extern void objc_free_class(Class);
 extern void objc_free_all_classes(void);
 extern uint32_t objc_hash_string(const char*);
 extern struct objc_hashtable* objc_hashtable_new(uint32_t);
 extern void objc_hashtable_set(struct objc_hashtable*, const char*,
     const void*);

Index: src/runtime/sparsearray.m
==================================================================
--- src/runtime/sparsearray.m
+++ src/runtime/sparsearray.m
@@ -194,14 +194,14 @@
 #ifdef OF_SELUID24
 	uint_fast16_t j;
 #endif
 
 	for (i = 0; i < 256; i++) {
-#ifdef OF_SELUID24
 		if (s->buckets[i]->empty)
 			continue;
 
+#ifdef OF_SELUID24
 		for (j = 0; j < 256; j++)
 			if (!s->buckets[i]->buckets[j]->empty)
 				free(s->buckets[i]->buckets[j]);
 #endif
 

Index: tests/TestsAppDelegate.m
==================================================================
--- tests/TestsAppDelegate.m
+++ tests/TestsAppDelegate.m
@@ -13,10 +13,12 @@
  * LICENSE.GPLv2 or LICENSE.GPLv3 respectively included in the packaging of this
  * file.
  */
 
 #include "config.h"
+
+#include <stdlib.h>
 
 #import "OFString.h"
 #import "OFFile.h"
 #import "OFAutoreleasePool.h"
 
@@ -30,10 +32,14 @@
 #endif
 
 int
 main(int argc, char *argv[])
 {
+#ifdef OF_OBJFW_RUNTIME
+	atexit(objc_exit);
+#endif
+
 	/* We need deterministic hashes for tests */
 	of_hash_seed = 0;
 
 	return of_application_main(&argc, &argv, [TestsAppDelegate class]);
 }

Index: tests/plugin/TestPlugin.m
==================================================================
--- tests/plugin/TestPlugin.m
+++ tests/plugin/TestPlugin.m
@@ -15,10 +15,20 @@
  */
 
 #include "config.h"
 
 #import "TestPlugin.h"
+
+#ifdef OF_OBJFW_RUNTIME
+# import "runtime-private.h"
+
+static void __attribute__((destructor))
+unload(void)
+{
+	objc_free_class(objc_getClass("TestPlugin"));
+}
+#endif
 
 @implementation TestPlugin
 - (int)test: (int)num
 {
 	return num * 2;