From 5338ee2b43de51337ba7072c0e8ac601cd85f027 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20=C5=A0ach?= <martin.sachin@gmail.com>
Date: Tue, 17 Dec 2024 17:02:33 +0100
Subject: [PATCH] Fix SPE-2621: Add fallback if no first isntance is found,
 while the instances are not empty

---
 src/libslic3r/GCode/ExtrusionOrder.cpp | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/libslic3r/GCode/ExtrusionOrder.cpp b/src/libslic3r/GCode/ExtrusionOrder.cpp
index b1fdc1de8c..697739956a 100644
--- a/src/libslic3r/GCode/ExtrusionOrder.cpp
+++ b/src/libslic3r/GCode/ExtrusionOrder.cpp
@@ -729,6 +729,10 @@ const PrintInstance * get_first_instance(
     const std::vector<ExtruderExtrusions> &extrusions,
     const std::vector<InstanceToPrint> &instances_to_print
 ) {
+    if (instances_to_print.empty()) {
+        return nullptr;
+    }
+
     for (const ExtruderExtrusions &extruder_extrusions : extrusions) {
         if (!extruder_extrusions.overriden_extrusions.empty()) {
             for (std::size_t i{0}; i < instances_to_print.size(); ++i) {
@@ -749,7 +753,8 @@ const PrintInstance * get_first_instance(
             }
         }
     }
-    return nullptr;
+    const InstanceToPrint &instance{instances_to_print.front()};
+    return &instance.print_object.instances()[instance.instance_id];
 }
 
 }