@@ -18,12 +18,10 @@
 
 #include <stdint.h>
 #include <stdlib.h>
 #include <string.h>
 
-#include <assert.h>
-
 #if defined(OF_APPLE_RUNTIME) && !defined(__OBJC2__)
 # import <objc/runtime.h>
 #elif defined(OF_OBJFW_RUNTIME)
 # import "runtime-private.h"
 #endif
@@ -32,10 +30,11 @@
 
 #import "OFAllocFailedException.h"
 #import "OFInitializationFailedException.h"
 #import "OFNotImplementedException.h"
 
+#import "macros.h"
 #ifdef OF_ATOMIC_OPS
 # import "atomic.h"
 #endif
 #ifdef OF_THREADS
 # import "threading.h"
@@ -199,13 +198,13 @@
 #if defined(OF_ATOMIC_OPS)
 		of_atomic_inc_int(&block->flags);
 #else
 		unsigned hash = SPINLOCK_HASH(block);
 
-		assert(of_spinlock_lock(&spinlocks[hash]));
+		OF_ENSURE(of_spinlock_lock(&spinlocks[hash]));
 		block->flags++;
-		assert(of_spinlock_unlock(&spinlocks[hash]));
+		OF_ENSURE(of_spinlock_unlock(&spinlocks[hash]));
 #endif
 	}
 
 	return block;
 }
@@ -226,22 +225,22 @@
 		free(block);
 	}
 #else
 	unsigned hash = SPINLOCK_HASH(block);
 
-	assert(of_spinlock_lock(&spinlocks[hash]));
+	OF_ENSURE(of_spinlock_lock(&spinlocks[hash]));
 	if ((--block->flags & OF_BLOCK_REFCOUNT_MASK) == 0) {
-		assert(of_spinlock_unlock(&spinlocks[hash]));
+		OF_ENSURE(of_spinlock_unlock(&spinlocks[hash]));
 
 		if (block->flags & OF_BLOCK_HAS_COPY_DISPOSE)
 			block->descriptor->dispose_helper(block);
 
 		free(block);
 
 		return;
 	}
-	assert(of_spinlock_unlock(&spinlocks[hash]));
+	OF_ENSURE(of_spinlock_unlock(&spinlocks[hash]));
 #endif
 }
 
 void
 _Block_object_assign(void *dst_, const void *src_, const int flags_)