diff --git a/src/p_acs.h b/src/p_acs.h
index 8ccf629820..fc361a230f 100644
--- a/src/p_acs.h
+++ b/src/p_acs.h
@@ -129,7 +129,7 @@ private:
 	{
 		FString Str;
 		unsigned int Hash;
-		unsigned int Next;
+		unsigned int Next = FREE_ENTRY;
 		bool Mark;
 		TArray<int> Locks;