diff --git a/src/regexp_nfa.c b/src/regexp_nfa.c
index 5414465..47d7030 100644
--- a/src/regexp_nfa.c
+++ b/src/regexp_nfa.c
@@ -4210,6 +4210,8 @@
 
     /* re-order to put the new state at the current position */
     count = l->n - tlen;
+    if (count == 0)
+	return; /* no state got added */
     if (count == 1)
     {
 	/* overwrite the current state */