diff --git a/lib/plist.c b/lib/plist.c
index b447bda2..5c8e71a2 100644
--- a/lib/plist.c
+++ b/lib/plist.c
@@ -103,7 +103,7 @@ xbps_array_foreach_cb_multi(struct xbps_handle *xhp,
 	struct thread_data *thd;
 	unsigned int arraycount, slicecount;
 	int rv = 0, maxthreads;
-	unsigned int reserved = 0;
+	unsigned int reserved;
 	pthread_spinlock_t reserved_lock;
 
 	assert(fn != NULL);
@@ -138,6 +138,8 @@ xbps_array_foreach_cb_multi(struct xbps_handle *xhp,
 		}
 	}
 
+	reserved = slicecount * maxthreads;
+
 	for (int i = 0; i < maxthreads; i++) {
 		thd[i].array = array;
 		thd[i].dict = dict;