- splay_insert(edge_weight_tree, e);
- splay_insert(e->from->edge_tree, e);
+ splay_node_t *node = splay_insert(e->from->edge_tree, e);
+
+ if(!node) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Edge from %s to %s already exists in edge_tree\n", e->from->name, e->to->name);
+ return;
+ }
+