From 6cec876a412332b1f057dca4c0482d07dbf993e0 Mon Sep 17 00:00:00 2001
From: Florian Foinant-Willig <flachyjoe@gmail.com>
Date: Tue, 12 Mar 2024 21:47:07 +0100
Subject: [PATCH] [Link] Fix SIGSEGV with LinkCopyOnChange=Tracking

---
 src/App/Link.cpp | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/App/Link.cpp b/src/App/Link.cpp
index 4328a2ebe1..088143bfb5 100644
--- a/src/App/Link.cpp
+++ b/src/App/Link.cpp
@@ -319,6 +319,12 @@ App::DocumentObjectExecReturn *LinkBaseExtension::extensionExecute() {
             syncCopyOnChange();
         }
 
+        // the previous linked object could be deleted by syncCopyOnChange - #12281
+        linked = getTrueLinkedObject(true);
+        if(!linked) {
+            return new App::DocumentObjectExecReturn("Error in processing variable link");
+        }
+
         PropertyPythonObject *proxy = nullptr;
         if(getLinkExecuteProperty()
                 && !boost::iequals(getLinkExecuteValue(), "none")