From 942f8bbf058c59aab091455771f0dfbbc3420d98 Mon Sep 17 00:00:00 2001
From: Ivan Savenko <saven.ivan@gmail.com>
Date: Thu, 10 Aug 2023 21:18:52 +0300
Subject: [PATCH] Fix possible access to non-existing building

---
 lib/mapObjects/CGTownInstance.cpp | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/lib/mapObjects/CGTownInstance.cpp b/lib/mapObjects/CGTownInstance.cpp
index 4f088b414..10fd30409 100644
--- a/lib/mapObjects/CGTownInstance.cpp
+++ b/lib/mapObjects/CGTownInstance.cpp
@@ -996,6 +996,12 @@ CBuilding::TRequired CGTownInstance::genBuildingRequirements(const BuildingID &
 	std::function<CBuilding::TRequired::Variant(const BuildingID &)> dependTest =
 	[&](const BuildingID & id) -> CBuilding::TRequired::Variant
 	{
+		if (town->buildings.count(id) == 0)
+		{
+			logMod->error("Invalid building ID %d in building dependencies!", id.getNum());
+			return CBuilding::TRequired::OperatorAll();
+		}
+
 		const CBuilding * build = town->buildings.at(id);
 		CBuilding::TRequired::OperatorAll requirements;