diff --git a/src/regexp.h b/src/regexp.h
index 976927e..84e8d19 100644
--- a/src/regexp.h
+++ b/src/regexp.h
@@ -101,7 +101,7 @@
 #endif
     int			nsubexp;	/* number of () */
     int			nstate;
-    nfa_state_T		state[0];	/* actually longer.. */
+    nfa_state_T		state[1];	/* actually longer.. */
 } nfa_regprog_T;
 
 /*