From c91a21d42b4a8eaa80e953a4ce7935fe7d54d545 Mon Sep 17 00:00:00 2001
From: Jacques Lucke <jacques@blender.org>
Date: Thu, 31 Jul 2025 22:06:30 +0200
Subject: [PATCH] Fix: Geometry Nodes: crash when linking closure/bundle to
 group in/output extent socket

The issue was that the parent node group was not necessarily updated already
when the tracing code ran. So use socket identifiers instead of indices to try
to find corresponding sockets between group nodes and their corresponding
node groups.
---
 source/blender/nodes/intern/trace_values.cc | 30 ++++++++++++++-------
 1 file changed, 21 insertions(+), 9 deletions(-)

diff --git a/source/blender/nodes/intern/trace_values.cc b/source/blender/nodes/intern/trace_values.cc
index 7b183a038d0..566cfce1a6d 100644
--- a/source/blender/nodes/intern/trace_values.cc
+++ b/source/blender/nodes/intern/trace_values.cc
@@ -91,9 +91,12 @@ static Vector<SocketInContext> find_target_sockets_through_contexts(
           const ComputeContext &group_compute_context = compute_context_cache.for_group_node(
               socket.context, node->identifier, &node->owner_tree());
           for (const bNode *input_node : group->group_input_nodes()) {
-            const bNodeSocket &group_input_socket = input_node->output_socket(socket->index());
-            if (group_input_socket.is_directly_linked()) {
-              add_if_new({&group_compute_context, &group_input_socket}, bundle_path);
+            if (const bNodeSocket *group_input_socket = input_node->output_by_identifier(
+                    socket->identifier))
+            {
+              if (group_input_socket->is_directly_linked()) {
+                add_if_new({&group_compute_context, group_input_socket}, bundle_path);
+              }
             }
           }
         }
@@ -107,8 +110,11 @@ static Vector<SocketInContext> find_target_sockets_through_contexts(
           const bNode *caller_group_node = group_context->node();
           if (caller_group && caller_group_node) {
             caller_group->ensure_topology_cache();
-            const bNodeSocket &output_socket = caller_group_node->output_socket(socket->index());
-            add_if_new({group_context->parent(), &output_socket}, bundle_path);
+            if (const bNodeSocket *output_socket = caller_group_node->output_by_identifier(
+                    socket->identifier))
+            {
+              add_if_new({group_context->parent(), output_socket}, bundle_path);
+            }
           }
         }
         continue;
@@ -341,8 +347,11 @@ static Vector<SocketInContext> find_origin_sockets_through_contexts(
           if (const bNode *group_output_node = group->group_output_node()) {
             const ComputeContext &group_compute_context = compute_context_cache.for_group_node(
                 socket.context, node->identifier, &node->owner_tree());
-            add_if_new({&group_compute_context, &group_output_node->input_socket(socket->index())},
-                       bundle_path);
+            if (const bNodeSocket *group_output_socket = group_output_node->input_by_identifier(
+                    socket->identifier))
+            {
+              add_if_new({&group_compute_context, group_output_socket}, bundle_path);
+            }
           }
         }
         continue;
@@ -355,8 +364,11 @@ static Vector<SocketInContext> find_origin_sockets_through_contexts(
           const bNode *caller_group_node = group_context->node();
           if (caller_group && caller_group_node) {
             caller_group->ensure_topology_cache();
-            const bNodeSocket &input_socket = caller_group_node->input_socket(socket->index());
-            add_if_new({group_context->parent(), &input_socket}, bundle_path);
+            if (const bNodeSocket *input_socket = caller_group_node->input_by_identifier(
+                    socket->identifier))
+            {
+              add_if_new({group_context->parent(), input_socket}, bundle_path);
+            }
           }
         }
         continue;