diff --git a/py/objlist.c b/py/objlist.c
index 789a160..1531b6b 100644
--- a/py/objlist.c
+++ b/py/objlist.c
@@ -164,7 +164,7 @@
                 assert(0);
             }
 
-            int len_adj = slice.start - slice.stop;
+            mp_int_t len_adj = slice.start - slice.stop;
             //printf("Len adj: %d\n", len_adj);
             assert(len_adj <= 0);
             mp_seq_replace_slice_no_grow(self->items, self->len, slice.start, slice.stop, self->items/*NULL*/, 0, mp_obj_t);
@@ -203,7 +203,7 @@
             if (!mp_seq_get_fast_slice_indexes(self->len, index, &slice_out)) {
                 assert(0);
             }
-            int len_adj = slice->len - (slice_out.stop - slice_out.start);
+            mp_int_t len_adj = slice->len - (slice_out.stop - slice_out.start);
             //printf("Len adj: %d\n", len_adj);
             if (len_adj > 0) {
                 if (self->len + len_adj > self->alloc) {