diff --git a/src/ex_docmd.c b/src/ex_docmd.c
index 71a7b1b..701354e 100644
--- a/src/ex_docmd.c
+++ b/src/ex_docmd.c
@@ -9300,7 +9300,7 @@
 		  break;
 	default:			/* ":tag" */
 #ifdef FEAT_CSCOPE
-		  if (p_cst)
+		  if (p_cst && *eap->arg != NUL)
 		  {
 		      do_cstag(eap);
 		      return;