diff --git a/src/ex_cmds.c b/src/ex_cmds.c
index b2aaf1c..acddd9c 100644
--- a/src/ex_cmds.c
+++ b/src/ex_cmds.c
@@ -3841,11 +3841,11 @@
 	    which_pat = RE_LAST;	    // use last used regexp
 	    delimiter = *cmd++;		    // remember delimiter character
 	    pat = cmd;			    // remember start of search pat
-	    patlen = STRLEN(pat);
 	    cmd = skip_regexp_ex(cmd, delimiter, magic_isset(),
 							&eap->arg, NULL, NULL);
 	    if (cmd[0] == delimiter)	    // end delimiter found
 		*cmd++ = NUL;		    // replace it with a NUL
+	    patlen = STRLEN(pat);
 	}
 
 	/*