From 02f41bbe60ccc8bd3f9dd35531413bc5078147e7 Mon Sep 17 00:00:00 2001
From: wmayer <wmayer@freecad.org>
Date: Fri, 20 Dec 2024 22:18:10 +0100
Subject: [PATCH] App: Fix possible crash when postponing the destruction of a
 removed property

Fixes #18601
---
 src/App/Property.cpp     |  1 +
 src/Mod/Test/Document.py | 19 +++++++++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/src/App/Property.cpp b/src/App/Property.cpp
index 2b20f8f166..904d91f8ce 100644
--- a/src/App/Property.cpp
+++ b/src/App/Property.cpp
@@ -213,6 +213,7 @@ struct PropertyCleaner
             auto p = _RemovedProps.back();
             _RemovedProps.pop_back();
             if (p != prop) {
+                p->setContainer(nullptr);
                 delete p;
             }
             else {
diff --git a/src/Mod/Test/Document.py b/src/Mod/Test/Document.py
index e59ab99e78..4959650789 100644
--- a/src/Mod/Test/Document.py
+++ b/src/Mod/Test/Document.py
@@ -44,6 +44,16 @@ class Proxy:
         self.Dictionary = data
 
 
+class MyFeature:
+    def __init__(self, obj):
+        obj.Proxy = self
+        obj.addProperty("App::PropertyLinkList", "propLink")
+
+    def onDocumentRestored(self, obj):
+        if hasattr(obj, "propLink"):
+            obj.removeProperty("propLink")
+
+
 class DocumentBasicCases(unittest.TestCase):
     def setUp(self):
         self.Doc = FreeCAD.newDocument("CreateTest")
@@ -56,6 +66,15 @@ class DocumentBasicCases(unittest.TestCase):
         self.Doc = FreeCAD.open(SaveName)
         return self.Doc
 
+    def testIssue18601(self):
+        lnk = self.Doc.addObject("App::FeaturePython", "MyLink")
+        obj = self.Doc.addObject("App::FeaturePython", "MyFeature")
+        fea = MyFeature(obj)
+        obj.propLink = [lnk]
+        doc = self.saveAndRestore()
+        FreeCAD.closeDocument(doc.Name)
+        self.Doc = FreeCAD.newDocument("CreateTest")
+
     def testAccessByNameOrID(self):
         obj = self.Doc.addObject("App::DocumentObject", "MyName")