diff --git a/src/saveload/oldloader.cpp b/src/saveload/oldloader.cpp
index ff911a899e..83fc58ebfa 100644
--- a/src/saveload/oldloader.cpp
+++ b/src/saveload/oldloader.cpp
@@ -244,7 +244,7 @@ static inline bool CheckOldSavegameType(FILE *f, char *temp, const char *last, u
 static SavegameType DetermineOldSavegameType(FILE *f, char *title, const char *last)
 {
 	assert_compile(TTD_HEADER_SIZE >= TTO_HEADER_SIZE);
-	char temp[TTD_HEADER_SIZE];
+	char temp[TTD_HEADER_SIZE] = "Unknown";
 
 	SavegameType type = SGT_TTO;