Index: src/OFThread.h
==================================================================
--- src/OFThread.h
+++ src/OFThread.h
@@ -71,11 +71,13 @@
 	enum of_thread_running {
 		OF_THREAD_NOT_RUNNING,
 		OF_THREAD_RUNNING,
 		OF_THREAD_WAITING_FOR_JOIN
 	} _running;
+# ifndef OF_OBJFW_RUNTIME
 	void *_pool;
+# endif
 # ifdef OF_HAVE_BLOCKS
 	of_thread_block_t _Nullable _threadBlock;
 # endif
 	jmp_buf _exitEnv;
 	id _returnValue;

Index: src/OFThread.m
==================================================================
--- src/OFThread.m
+++ src/OFThread.m
@@ -105,11 +105,13 @@
 
 	if (!of_tlskey_set(threadSelfKey, thread))
 		@throw [OFInitializationFailedException
 		    exceptionWithClass: thread.class];
 
+#ifndef OF_OBJFW_RUNTIME
 	thread->_pool = objc_autoreleasePoolPush();
+#endif
 
 	name = thread.name;
 	if (name != nil)
 		of_thread_set_name(
 		    [name cStringWithEncoding: [OFLocale encoding]]);
@@ -136,11 +138,15 @@
 			thread->_returnValue = [[thread main] retain];
 	}
 
 	[thread handleTermination];
 
+#ifdef OF_OBJFW_RUNTIME
+	objc_autoreleasePoolPop((void *)(uintptr_t)-1);
+#else
 	objc_autoreleasePoolPop(thread->_pool);
+#endif
 
 #if defined(OF_AMIGAOS) && defined(OF_HAVE_SOCKETS)
 	if (thread.supportsSockets)
 		of_socket_deinit();
 #endif

Index: src/runtime/autorelease.m
==================================================================
--- src/runtime/autorelease.m
+++ src/runtime/autorelease.m
@@ -27,109 +27,107 @@
 # import "tlskey.h"
 #endif
 
 #if defined(OF_HAVE_COMPILER_TLS)
 static thread_local id *objects = NULL;
-static thread_local id *top = NULL;
-static thread_local size_t size = 0;
+static thread_local uintptr_t count = 0;
+static thread_local uintptr_t size = 0;
 #elif defined(OF_HAVE_THREADS)
-static of_tlskey_t objectsKey, topKey, sizeKey;
+static of_tlskey_t objectsKey, countKey, sizeKey;
 #else
 static id *objects = NULL;
-static id *top = NULL;
-static size_t size = 0;
+static uintptr_t count = 0;
+static uintptr_t size = 0;
 #endif
 
 #if !defined(OF_HAVE_COMPILER_TLS) && defined(OF_HAVE_THREADS)
 OF_CONSTRUCTOR()
 {
 	OF_ENSURE(of_tlskey_new(&objectsKey));
-	OF_ENSURE(of_tlskey_new(&topKey));
+	OF_ENSURE(of_tlskey_new(&countKey));
 	OF_ENSURE(of_tlskey_new(&sizeKey));
 }
 #endif
 
 void *
 objc_autoreleasePoolPush()
 {
 #if !defined(OF_HAVE_COMPILER_TLS) && defined(OF_HAVE_THREADS)
-	id *top = of_tlskey_get(topKey);
-	id *objects = of_tlskey_get(objectsKey);
+	uintptr_t count = (uintptr_t)of_tlskey_get(countKey);
 #endif
-	ptrdiff_t offset = top - objects;
-
-	return (void *)offset;
+	return (void *)count;
 }
 
 void
-objc_autoreleasePoolPop(void *offset)
-{
-#if !defined(OF_HAVE_COMPILER_TLS) && defined(OF_HAVE_THREADS)
-	id *top = of_tlskey_get(topKey);
-	id *objects = of_tlskey_get(objectsKey);
-#endif
-	id *pool = objects + (ptrdiff_t)offset;
-	id *iter;
-
-	for (iter = pool; iter < top; iter++)
-		[*iter release];
-
-	top = pool;
-
-	if (top == objects) {
-		free(objects);
-
-		objects = NULL;
-		top = NULL;
-	}
-
-#if !defined(OF_HAVE_COMPILER_TLS) && defined(OF_HAVE_THREADS)
-	OF_ENSURE(of_tlskey_set(topKey, top));
-	OF_ENSURE(of_tlskey_set(objectsKey, objects));
+objc_autoreleasePoolPop(void *pool)
+{
+#if !defined(OF_HAVE_COMPILER_TLS) && defined(OF_HAVE_THREADS)
+	id *objects = of_tlskey_get(objectsKey);
+	uintptr_t count = (uintptr_t)of_tlskey_get(countKey);
+#endif
+	uintptr_t idx = (uintptr_t)pool;
+	bool freeMem = false;
+
+	if (idx == (uintptr_t)-1) {
+		idx++;
+		freeMem = true;
+	}
+
+	for (uintptr_t i = idx; i < count; i++) {
+		[objects[i] release];
+
+#if !defined(OF_HAVE_COMPILER_TLS) && defined(OF_HAVE_THREADS)
+		objects = of_tlskey_get(objectsKey);
+		count = (uintptr_t)of_tlskey_get(countKey);
+#endif
+	}
+
+	count = idx;
+
+	if (freeMem) {
+		free(objects);
+		objects = NULL;
+#if defined(OF_HAVE_COMPILER_TLS) || !defined(OF_HAVE_THREADS)
+		size = 0;
+#else
+		OF_ENSURE(of_tlskey_set(objectsKey, objects));
+		OF_ENSURE(of_tlskey_set(sizeKey, (void *)0));
+#endif
+	}
+
+#if !defined(OF_HAVE_COMPILER_TLS) && defined(OF_HAVE_THREADS)
+	OF_ENSURE(of_tlskey_set(countKey, (void *)count));
 #endif
 }
 
 id
 _objc_rootAutorelease(id object)
 {
 #if !defined(OF_HAVE_COMPILER_TLS) && defined(OF_HAVE_THREADS)
-	id *top = of_tlskey_get(topKey);
-	id *objects = of_tlskey_get(objectsKey);
-	size_t size = (size_t)(uintptr_t)of_tlskey_get(sizeKey);
-#endif
-
-	if (objects == NULL) {
-		size = 16 * sizeof(id);
-
-		OF_ENSURE((objects = malloc(size)) != NULL);
-
-		top = objects;
-
-#if !defined(OF_HAVE_COMPILER_TLS) && defined(OF_HAVE_THREADS)
-		OF_ENSURE(of_tlskey_set(objectsKey, objects));
-		OF_ENSURE(of_tlskey_set(sizeKey, (void *)(uintptr_t)size));
-#endif
-	}
-
-	if ((uintptr_t)top >= (uintptr_t)objects + size) {
-		ptrdiff_t diff = top - objects;
-
-		size *= 2;
-		OF_ENSURE((objects = realloc(objects, size)) != NULL);
-
-#if !defined(OF_HAVE_COMPILER_TLS) && defined(OF_HAVE_THREADS)
-		OF_ENSURE(of_tlskey_set(objectsKey, objects));
-		OF_ENSURE(of_tlskey_set(sizeKey, (void *)(uintptr_t)size));
-#endif
-
-		top = objects + diff;
-	}
-
-	*top = object;
-	top++;
-
-#if !defined(OF_HAVE_COMPILER_TLS) && defined(OF_HAVE_THREADS)
-	OF_ENSURE(of_tlskey_set(topKey, top));
+	id *objects = of_tlskey_get(objectsKey);
+	uintptr_t count = (uintptr_t)of_tlskey_get(countKey);
+	uintptr_t size = (uintptr_t)of_tlskey_get(sizeKey);
+#endif
+
+	if (count >= size) {
+		if (size == 0)
+			size = 16;
+		else
+			size *= 2;
+
+		OF_ENSURE((objects =
+		    realloc(objects, size * sizeof(id))) != NULL);
+
+#if !defined(OF_HAVE_COMPILER_TLS) && defined(OF_HAVE_THREADS)
+		OF_ENSURE(of_tlskey_set(objectsKey, objects));
+		OF_ENSURE(of_tlskey_set(sizeKey, (void *)size));
+#endif
+	}
+
+	objects[count++] = object;
+
+#if !defined(OF_HAVE_COMPILER_TLS) && defined(OF_HAVE_THREADS)
+	OF_ENSURE(of_tlskey_set(countKey, (void *)count));
 #endif
 
 	return object;
 }