diff -r 4523f6d42512 -r 741a2040fa33 src/array_list.c
--- a/src/array_list.c	Mon Dec 18 16:04:21 2023 +0100
+++ b/src/array_list.c	Mon Dec 18 16:14:07 2023 +0100
@@ -27,6 +27,7 @@
  */
 
 #include "cx/array_list.h"
+#include "cx/compare.h"
 #include <assert.h>
 #include <string.h>
 
@@ -522,13 +523,14 @@
 
     list->base.cl = &cx_array_list_class;
     list->base.allocator = allocator;
-    list->base.cmpfunc = comparator;
     list->capacity = initial_capacity;
 
     if (item_size > 0) {
         list->base.item_size = item_size;
+        list->base.cmpfunc = comparator;
     } else {
         item_size = sizeof(void *);
+        list->base.cmpfunc = comparator == NULL ? cx_cmp_ptr : comparator;
         cxListStorePointers((CxList *) list);
     }