GH-124567: Replace quadratic assert with linear one (GH-127009)

diff --git a/Python/gc.c b/Python/gc.c
index fe81ca5989c621e01435d7807de5c2fec9313781..a774183c49d1210cf0341992165d5e8d6127bdac 100644 (file)
--- a/Python/gc.c
+++ b/Python/gc.c
@@ -1394,7 +1394,6 @@ visit_add_to_container(PyObject *op, void *arg)
 static uintptr_t
 expand_region_transitively_reachable(PyGC_Head *container, PyGC_Head *gc, GCState *gcstate)
 {
-    validate_list(container, collecting_clear_unreachable_clear);
     struct container_and_flag arg = {
         .container = container,
         .visited_space = gcstate->visited_space,
@@ -1468,6 +1467,7 @@ gc_collect_increment(PyThreadState *tstate, struct gc_collection_stats *stats)
         gc_set_old_space(gc, gcstate->visited_space);
         increment_size += expand_region_transitively_reachable(&increment, gc, gcstate);
     }
+    validate_list(&increment, collecting_clear_unreachable_clear);
     gc_list_validate_space(&increment, gcstate->visited_space);
     PyGC_Head survivors;
     gc_list_init(&survivors);