From 4ccd860b2f6096b67610c7ae163cb8592c6fb813 Mon Sep 17 00:00:00 2001
From: Ivan Savenko <saven.ivan@gmail.com>
Date: Fri, 3 Jan 2025 15:41:26 +0000
Subject: [PATCH] Fix possible crash on loading save with invalid buildings,
 e.g. Mage Guild 4 in towns without one

---
 lib/mapObjects/CGTownInstance.cpp | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/lib/mapObjects/CGTownInstance.cpp b/lib/mapObjects/CGTownInstance.cpp
index e9ca3c9cd..819d15723 100644
--- a/lib/mapObjects/CGTownInstance.cpp
+++ b/lib/mapObjects/CGTownInstance.cpp
@@ -1247,6 +1247,14 @@ void CGTownInstance::postDeserialize()
 	setNodeType(CBonusSystemNode::TOWN);
 	for(auto & building : rewardableBuildings)
 		building.second->town = this;
+
+	if (getFactionID().hasValue())
+	{
+		vstd::erase_if(builtBuildings, [this](const BuildingID & buildID)
+		{
+			return getTown()->buildings.count(buildID) == 0;
+		});
+	}
 }
 
 std::map<BuildingID, TownRewardableBuildingInstance*> CGTownInstance::convertOldBuildings(std::vector<TownRewardableBuildingInstance*> oldVector)