diff --git a/src/quickfix.c b/src/quickfix.c
index 868b5d9..00457e2 100644
--- a/src/quickfix.c
+++ b/src/quickfix.c
@@ -4520,7 +4520,7 @@
 	*dirname = NUL;
 
 	// Add one line for each error
-	if (old_last == NULL)
+	if (old_last == NULL || old_last->qf_next == NULL)
 	{
 	    qfp = qfl->qf_start;
 	    lnum = 0;