diff --git a/Zend/zend_enum.c b/Zend/zend_enum.c
index 59befde732194..9ec444e4c75e3 100644
--- a/Zend/zend_enum.c
+++ b/Zend/zend_enum.c
@@ -409,8 +409,11 @@ static void zend_enum_register_func(zend_class_entry *ce, zend_known_string_id n
 	zif->module = EG(current_module);
 	zif->scope = ce;
 	zif->T = ZEND_OBSERVER_ENABLED;
-	ZEND_MAP_PTR_NEW(zif->run_time_cache);
-	ZEND_MAP_PTR_SET(zif->run_time_cache, zend_arena_alloc(&CG(arena), zend_internal_run_time_cache_reserved_size()));
+    if (EG(active)) { // at run-time: this ought to only happen if registered with dl() or somehow temporarily at runtime
+		ZEND_MAP_PTR_INIT(zif->run_time_cache, zend_arena_alloc(&CG(arena), zend_internal_run_time_cache_reserved_size()));
+	} else {
+		ZEND_MAP_PTR_NEW(zif->run_time_cache);
+	}
 
 	if (!zend_hash_add_ptr(&ce->function_table, name, zif)) {
 		zend_error_noreturn(E_COMPILE_ERROR, "Cannot redeclare %s::%s()", ZSTR_VAL(ce->name), ZSTR_VAL(name));