From ed75592979367b8b2e61d003022ea638af1177a1 Mon Sep 17 00:00:00 2001
From: Jonathan G Rennison <j.g.rennison@gmail.com>
Date: Fri, 22 Sep 2023 16:56:19 +0100
Subject: [PATCH] Fix crash attempting to remove sprite zoom level from empty
 entry

---
 src/spritecache.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/spritecache.cpp b/src/spritecache.cpp
index 964bcc71380..b08231aaf10 100644
--- a/src/spritecache.cpp
+++ b/src/spritecache.cpp
@@ -125,6 +125,9 @@ struct SpriteCache {
 	void RemoveByMissingZoomLevels(uint8 lvls)
 	{
 		Sprite *base = this->GetSpritePtr();
+		if (base == nullptr) {
+			return;
+		}
 		if (base->missing_zoom_levels == lvls) {
 			/* erase top level entry */
 			this->ptr.reset(base->next);