diff --git a/src/newgrf_config.cpp b/src/newgrf_config.cpp
index 3a4c0cb448..f09a571fc3 100644
--- a/src/newgrf_config.cpp
+++ b/src/newgrf_config.cpp
@@ -406,6 +406,7 @@ void ScanNewGRFFiles()
 	}
 
 	DEBUG(grf, 1, "Scan complete, found %d files", num);
+	if (num == 0 || _all_grfs == NULL) return;
 
 	/* Sort the linked list using quicksort.
 	 * For that we first have to make an array, the qsort and