diff --git a/arc.mm b/arc.mm
index 4070017..4873fa8 100644
--- a/arc.mm
+++ b/arc.mm
@@ -629,9 +629,21 @@ namespace {
 struct WeakRef
 {
 	void *isa = &weakref_class;
-	id obj = nullptr;
-	size_t weak_count = 1;
-	WeakRef(id o) : obj(o) {}
+	id object;
+	struct
+	{
+		size_t weak_count:((sizeof(size_t) * 8) - 1);
+		bool isDeleted:1;
+	};
+	id obj()
+	{
+		if (isDeleted)
+		{
+			return nil;
+		}
+		return object;
+	}
+	WeakRef(id o) : object(o), weak_count(1), isDeleted(false) {}
 };
 
 template<typename T>
@@ -709,7 +721,7 @@ static BOOL loadWeakPointer(id *addr, id *obj, WeakRef **ref)
 	if (classForObject(oldObj) == (Class)&weakref_class)
 	{
 		*ref = (WeakRef*)oldObj;
-		*obj = (*ref)->obj;
+		*obj = (*ref)->obj();
 		return YES;
 	}
 	*ref = NULL;
@@ -723,7 +735,7 @@ static inline BOOL weakRefRelease(WeakRef *ref)
 	ref->weak_count--;
 	if (ref->weak_count == 0)
 	{
-		weakRefs().erase(ref->obj);
+		weakRefs().erase(ref->object);
 		delete ref;
 		return YES;
 	}
@@ -786,7 +798,7 @@ WeakRef *incrementWeakRefCount(id obj)
 	}
 	else
 	{
-		assert(ref->obj == obj);
+		assert(ref->obj() == obj);
 		ref->weak_count++;
 	}
 	return ref;
@@ -862,7 +874,7 @@ extern "C" OBJC_PUBLIC BOOL objc_delete_weak_refs(id obj)
 		// accesses from loading from this.  This must be done after
 		// removing the ref from the table, because the compare operation
 		// tests the obj field.
-		oldRef->obj = nil;
+		oldRef->isDeleted = true;
 		// If the weak reference count is zero, then we should have
 		// already removed this.
 		assert(oldRef->weak_count > 0);