diff -r 872ae61c8945 -r 6d7aa8a1a3b3 src/ucx/array.h
--- a/src/ucx/array.h	Thu Jul 04 21:31:45 2019 +0200
+++ b/src/ucx/array.h	Thu Jul 04 22:23:15 2019 +0200
@@ -276,17 +276,15 @@
 int ucx_array_contains(UcxArray array, void *elem, cmp_func cmpfnc, void *data);
 
 /**
- * Sorts a UcxArray with natural merge sort.
+ * Sorts a UcxArray with an almost in-place merge sort.
  * 
- * This function uses O(n) additional temporary memory for merge operations
- * that is automatically freed after each merge.
+ * This function uses additional memory for exactly one element.
  * 
  * @param the array to sort
  * @param cmpfnc the function that shall be used to compare the element data
  * @param data additional data for the cmp_func()
- * @return zero on success, non-zero if allocation of temporary memory failed
  */
-int ucx_array_sort(UcxArray array, cmp_func cmpfnc, void *data);
+void ucx_array_sort(UcxArray array, cmp_func cmpfnc, void *data);
 
 /**
  * Removes an element from the array.